G-Donic Happiness: An Alternative to Hedonic and Eudemonic Happiness for Sustainable Consumption

: This paper provides a spiritual perspective on happiness referred to as the G-donic approach to happiness which is fundamentally different from the hedonic and eudemonic approaches. The G-donic approach identiﬁes the importance of the spiritual self and argues that it embodies the technology that converts physical resources into happiness. We argue that with G-donic preferences, it is possible to achieve a higher level of happiness with moderate consumption. The G-donic approach encourages living a virtuous life by fulﬁlling the biological, social, emotional, intellectual, moral, and spiritual needs in a balanced manner. It urges spiritual people to go beyond phenomenal reality to perceive transcendental reality in pursuit of authentic happiness. We use a multi-dimensional human nature model to highlight the relevance and importance of this approach, and modify standard utility models to show how it might result in higher happiness with lower consumption and compare and contrast it with outcomes under hedonic and eudemonic approaches to happiness. The G-donic approach contends that resources and spirituality are substitutes, as well as complements and that a reasonable approach to happiness should seek an optimal mix of both. Unlike popular convention, this deviation from hedonic pleasure due to lower consumption does not result in lower happiness. In fact, we show that, theoretically, it results in an overall increase in happiness as any loss in hedonic is compensated by greater eudemonic and G-donic rewards which increases utility.


Introduction
The history of happiness is as old as human history. Despite this, we are still searching for a better way to define and find happiness. Given the difficulty in defining happiness, psychologists refrain from using the term happiness and instead prefer to use the term well-being [1] or psychological well-being [2]. Modern literature on happiness is broadly divided into two major approaches: hedonic or eudemonic. The hedonic approach defines happiness as the maximization of pleasure/benefit and the minimization of pain/cost [3]. Utilitarianism offers hedonic calculus to calculate greater happiness with a greater amount of net pleasure. While the narrowly defined utilitarian approach focuses on flows of pleasure and pain from moment to moment, the comprehensive utilitarian approach puts emphasis on overall life satisfaction in terms of aggregate pain and pleasure. The eudemonic approach [4] considers virtue as the ultimate good, not pleasure. Therefore, it urges maximizing virtue to achieve a happy life [5]. For the hedonic model, a pleasant life is a happy one, while for the eudemonic model, a meaningful life is a happy one. The former defines happiness as the pursuit of pleasurable experiences, while the latter considers happiness as a state of having a good character.
Despite an extremely rich body of literature on both hedonic and eudemonic happiness, scholars are still not settled on the very definition of happiness. It is interesting to note that a great majority of the world comprises people of religion. According to the Pew Research Center, a nonpartisan fact tank that informs the public about the issues, attitudes and trends shaping the world, around 16% of the world population are agnostic or without a religion. Around two-thirds of the world's population subscribes to Abrahamic religions (Christianity, Islam, and Judaism) [6]. It is, however, interesting to see that the happiness literature does not have a well-defined religious perspective on happiness. A group of scholars from Saint Louis University was awarded a USD 5.1 million grant for three years in 2015 entitled "Happiness and Well-Being: Integrating Research Across the Disciplines" [1] to study happiness and well-being and promote dialogue and collaboration among well-being researchers across a wide range of disciplines, including the sciences, philosophy, and theology and religious studies [7]. A key innovation claimed by the project was the involvement of a theologian or religious scholar. Interestingly, however, the project's keynote speaker on religion and happiness, Ellen Charry, primarily considered religion as a threat to "global" happiness and highlighted the need for finding ways to moderate religious tendencies which could threaten global peace and happiness.
In this paper, we abstract away from the macro debate illuded to by Ellen Charry in her lecture at the project's capstone conference and present a religious approach to happiness using the Islamic worldview as an example. In particular, we discuss the meaning of happiness and what practical steps are taken by the religion of Islam to promote that notion of happiness. This is an important aspect that has been missing from the debate on religion and happiness. We argue that Islam identifies the spiritual self as the main source and target of happiness which is transcendental in nature. Islam refers to happiness as the tranquility of heart and reminds its believers that this can be achieved through "remembering" God and one's purpose in life. Islam encourages living a virtuous life by fulfilling biological, social, emotional, intellectual, moral, and spiritual needs in a balanced manner. This behavior is referred to as "pleasing God". We, therefore, refer to this type of happiness as G-donic happiness. This, of course, has similarities with other religions as well. We argue that the same framework can be used to understand how other religions define and promote happiness.
G-donic happiness also has relevance for, and parallels with, the positive psychology literature, popularized due to Seligman [8], which endeavors to look at elements of subjective well-being, which can be used as a guide to improve people's quality of life and improve their well-being. Wang [9] critically evaluates its application in treating patients with mental illness and argues that the old approach of focusing on psychopathology and Seligman's positive psychology approach will not be adequate and proposes an alternative approach which "emphasizes the need for enhancing the positives and managing the negatives in order to increase well-being and decrease mental illness." Whereas our characterization provides another element, that underlies subjective well-being, which can be used as a tool to treat individual patients, what is more interesting about the G-donic model is an inherent feature that continually primes its believers to remember their purpose in life and be conscious of the transcendental reality of their lives. They are constantly reminded that this life is a test and that they will be rewarded for being patient and following ideals of the religion and will be answerable for their acts. They consider apparent phenomena as shadows of transcendental reality which is pure and perfect. This is an important aspect as it is one way of enhancing the positives and managing the negatives at the society level which can be argued to increase well-being and decrease mental illness. We hope to explore this aspect of the G-donic model from a positive psychology point of view in future research.
The rest of the paper is structured as follows: First, we provide a brief overview of the literature on subjective well-being that relies on higher consumption. Second, we define G-donic happiness in general and with reference to core Islamic sources of guidance. Third, we discuss the importance of human nature within G-donic happiness. Fourth, we compare and contrast the hedonic, eudemonic, and G-donic models. Fifth, we provide a comparative illustration of utility functions that represent the three happiness models. Finally, we present several hypotheses to empirically test predictions of the G-donic happiness model.

Lower Subjective Well-Being with Higher Consumption
Profit-driven free-market capitalism has succeeded in implanting consumer culture around the world for the sake of making more money. However, as documented by many researchers, it has failed to bring the promised happiness. Indeed, consumer culture is not only destroying human happiness; it is also destroying the planet as suggested by many prominent scholars who drafted a Royal Society study in 2012 [10], which highlighted the dangers awaiting both people and the planet if the current consumer culture is not stopped. The report warned that "Rapid and widespread changes in the world's human population, coupled with unprecedented levels of consumption, present profound challenges to human health and well-being, and the natural environment." Twenty-two scientists who contributed to the report offered nine recommendations to prevent "social, economic and environmental failures and catastrophes on a scale never imagined" within 30-40 years. Seven out of nine recommendations were related to economic policies and systems to curb unsustainable consumer culture. The report openly called for the collaboration between National Governments to develop socio-economic systems and institutions that are not dependent on continued material consumption growth.
We argue that the search for happiness in a consumer society is largely one-dimensional by assuming that people would be happy with the fulfillment of biological needs and desires. Indeed, since the Enlightenment, in the West, the quest for happiness has been largely through material consumption. As capitalist consumer culture spreads around the world, hedonic happiness becomes the standard model for happiness. The dominant utilitarian view promises higher happiness through higher consumption. With the spread of mass media, consumer culture has reached every corner of the world. People began searching for happiness through engaging in conspicuous consumption [11][12][13]. Free market capitalism has turned people into consumption machines. As described by Haidt: "during the twentieth century, as people become wealthier and the producer society turned gradually into the mass consumption society, and an alternative vision of the self arose-a vision centered on the idea of individual preferences and personal fulfillment" [14] (p. 176).
Ironically, an unprecedented jump in real income per capita and consumption in the last few decades have not produced the promised paradise. Indeed, it was Easterlin [15] who first discovered the paradox between economic and subjective well-being at a national level. In his famous study, Easterlin found no correlation between income per capita and level of subjective well-being when comparing developed nations. Since Easterlin's study, the literature has flowed with the paradoxical relationship between economic wellbeing and subjective well-being at the national level [12,16,17]. It seems like conspicuous consumption is neither sustainable nor sufficient for higher subjective well-being. Some critics argue that it is a way of enslavement through the "iron cage of consumerism" [18] (p. 102).
As argued by Aydin [19,20], increasing consumption in modern times might be due to depletion of self-worth as a result of the secular paradigm, which considers humans as thinking animals with no intrinsic worth. Before the Enlightenment, human beings were considered to have the highest value among creation. A secular and materialistic worldview has discredited this innate value of humans. The emptied self is encouraged to fill up through material consumption to show worthiness in the eyes of beholders [21].
In this paper, we try to offer an alternative happiness model (G-donic) based on an Islamic worldview, which promotes a multi-dimensional understanding of human nature and happiness [22,23]. G-donic model urges believers to go beyond phenomenal reality to perceive transcendental reality in pursuit of authentic happiness. It argues that one can attain the highest happiness through God even when he/she does not have high material consumption. It encourages living a virtuous life by fulfilling biological, social, emotional, intellectual, moral, and spiritual needs in a balanced manner.
In short, despite its failure to bring happiness, consumer culture spreads around the world like COVID-19. No one seems to be immune from it. Muslims are not an exception despite the fact that their religion does offer an alternative way of happiness. We argue that despite scientific findings, people are misled by effective commercials to pursue happiness through higher consumption. Thus, in order to change the dominant consumer culture, we need to invite people to engage in critical thinking along with robust scientific studies.

Defining G-Donic Happiness
Belief in God is at the heart of religious commitments. Followers of Abrahamic religions believe in an All-Mighty God. They believe in guidance from God sent to them through prophets. Believers of all these religions see life as a test. The Quran, Bible, and Torah are full of statements that clearly state that this life is a test where believers are being tested in different aspects of life. See, for example, Deuteronomy 13:4, Genesis 22:1, James 1:2-4, 1 Peter 1:6-7, Quran 67:2 and Quran 2:155. They are expected to behave in a way that is consistent with the divine guidance they believe in. They also believe in a life after death where they will be judged based on their behavior in this world. This mindset plays an important role in determining their subjective well-being. Believers in these religions, like all other religions, perform regular rituals and rites which keep them connected with God. Muslims for example pray five times a day; Christens regularly go to churches; Jews pray three times a day. There is also a well-organized set of directives, ranging from obligatory to recommended and from prohibited to discouraged which guides their behavior in all aspects of life. We equate this behavior to seeking happiness in pleasing God by following divine guidance. We refer to this a G-donic happiness. Whereas it is possible to debate the depth and breadth of the belief system of all religions and debate as to how effective or deficient it is in promoting happiness, we will use Islam as a detailed example.
Islam puts a great emphasis on happiness. Indeed, Muslims name the age of their Prophet and their early rulers, referred to as the four righteous Caliphs, as the age of happiness (asr al-sa'adah). In the call for prayer (azan), Muslims are invited five times every day to pray and seek falah which means salvation and happiness. It, like other Abrahamic religions, promises its believers eternal happiness in the life after death if they put genuine effort in living a virtuous life. Thus, one might argue that Islam promotes itself as a religion of happiness in, both, this world and in the hereafter. Islam identifies the "spiritual self" as the main source of happiness. It associates true happiness with the natural tendency of humans to surrender to a purpose in life, as in eudemonic happiness. Its purpose in life is transcendental in nature. This is broadly referred to as "the remembrance of God" or seeking the pleasure of God.
The G-donic happiness perspective can be related to some verses of the Quran (the Holy Book of the Muslims) and ahadith (the sayings of the Prophet Mohammed) which are two primary references of Islamic teachings. Surat-ul Ra'd (verses [28][29], a chapter of the Quran, defines happiness as a state of the heart (spiritual faculty) that is "mutma-inn". The literal translation of the word "mutma-inn" is the following: "Reassured, tranquil, quiet, peaceful, calm, unconcerned, safe, secure, at ease." The first verse points to the contentment of heart through remembrance of God as the way to happiness in this world and the hereafter: "those who believe, and whose hearts find their rest in the remembrance of God-for, verily, in the remembrance of God, [men's] hearts do find their rest: [and so it is that] they who attain to faith and do righteous deeds are destined for happiness [in this world] and the most beauteous of all goals [in the life to come]!" 13:28-29 [24]. The phrase of "hearts find their rest through remembrance of God" is repeated twice in the same verse above to assure readers that indeed it is only through remembering God one can find true happiness. In other words, the Quran reinforces the same message by saying that the other ways to happiness lead to a depressed life: "And whoever turns away from My remembrance-indeed, he will have a depressed life, ..." [24].
The Quran constantly reminds believers of the importance of "remembering" God in all affairs of their lives. The Prophet Mohammed stated that remembrance of God is the most important to him than everything in the world: "The uttering of the words: "Subhan-Allah (Allah is free from imperfection), Al-hamdu lillah (all praise is due to Allah), La ilaha illallah (there is no true god except Allah) and Allahu Akbar (Allah is the Greatest)" is dearer to me than anything over which the sun rises" (Muslim, Book 16, Hadith 2). However, the "remembrance of God" does not refer to just the utterance of the word God, rather to a transcendental conscience in which one becomes aware of the ultimate reality behind the phenomenal one based on the Quranic teaching.
Authentic happiness, from an Islamic perspective, is not sensual or emotional feelings. It is not the state of mind. Rather, according to Al-Attas, "it has to do with certainty (yaqeen) of the ultimate truth and fulfillment of action in conformity with that certainty. And certainty is a permanent state of consciousness natural to what is permanent in man and perceived by his spiritual organ of cognition which is the heart (qalb). It is peace and security and tranquility of the heart (tuma'ninah); it is knowledge (ma'rifah) and knowledge is true faith (iman)" [25] (p. 36). It is a way of perceiving life events as a manifestation of God's names and live his/her life to please God. In the Quranic terms, those who ascend to this level would say the following: "For us God suffices, and He is the Best Disposer of Affairs" (The Quran, 3:173) [24]. In other words, for them, God is sufficient once they realize God-centered transcendental reality.
As stated by Al-Attas, Islam has its own vision of reality [25] (p. 75). Tawhidi worldview portrays a different vision of reality, which is centered on the Oneness of God. Becoming a believer is bear-witnessing this reality and living life accordingly. The goal is to read the book of the universe and feel the presence of God in everything. Indeed, a famous hadith describes ihsan (perfection) in life as follows: "One day while the Prophet was sitting in the company of some people, (The angel) Gabriel came and asked . . . . "What is Ihsan (perfection)?" Allah's Messenger replied, "To worship Allah as if you see Him, and if you cannot achieve this state of devotion then you must consider that He is looking at you." (Sahih al-Bukhari, Book 2, Hadith 43).
Islam, iman, and ihsan are three keywords summarizing the Islamic path to the highest happiness in this world and the hereafter. Islam is adherence to Islamic principles dealing with certain obligations toward God and humanity. Iman is an affirmation of the six pillars of faith as knowledge (marifaah). Ihsan is the highest level of iman in which one reaches certainty about the presence of God as if he sees Him. Thus, ihsan is the highest level of God's conscience. They all play a central role in achieving different levels of happiness.
Indeed, iman as an Arabic word is originated from the root of amn, which means calmness of the soul and freedom from fear. Thus, iman in the Islamic context means to be safe from any danger or fear in this life and the hereafter through believing in God as the only One who creates, controls, and sustains everything from moment to moment. Since, according to Islam, God is All-Good, All-Knowing, All-Powerful, Most-Just, Most-Merciful, once a believer reaches certainty in the existence and presence of God, there would be no room for true fear from dangers and fulfilling needs and desires.
In short, we argue that the Quran provides a different approach in defining happiness and providing guidance for a happy life to believers in this world and the hereafter. It identifies the "spiritual self" as the main source of happiness. It differs from both hedonic and eudemonic happiness models because it sets the ultimate goal for people as neither pleasure through higher consumption nor fulfillment through worldly success. Rather, it defines happiness as fulfillment through remembering God (being conscious of Him) and pursuing His pleasure through good deeds, i.e., living a life according to God's guidance.

G-Donic Happiness and Human Nature
The G-donic happiness model reflects on a comprehensive understanding of human nature from an Islamic perspective. As Prophet Mohammed says, "he who knows himself knows his Lord." In other words, knowing self is the key to knowing God. It is also the key to living a happy life in this world. According to prominent Muslim scholars such as Ghazali and Nursi, the human is neither good (angel) nor evil (Satan). A human is a unique creature with both angelic and Satanic tendencies. He needs to be aware of his positive and negative sides. His good side needs nourishment: "Each one of these qualities has its own distinct food that nourishes it, sustains and promotes its growth, resulting in the promotion of goodness and the approved behavior" [26] (p. 2). As stated in the Quran, the human is God's important project in the universe. The success of the project is measured by unleashing his positive sides while controlling the negative ones.
Inspired largely by the writings of some Muslim scholars such as Al-Ghazali and Nursi, Aydin [27] developed a theory of human nature: "A Grand Theory of Human Nature (GTHN). The theory defines human nature with its completing multi-dimensions based on Islamic teaching. It rejects the notion of self-interest, which is considered to be the invisible hand behind free-market system. Rather, the theory proposes multi-dimensional selves. Thus, it argues that one could not use the pronoun "I" any longer while defining one's happiness. There is not one entity as self. One should talk about selves, referring to the multiple selves within human nature. In this regard, we are not just a "reasoning self (mind/the Wazir)", we are also a "spiritual self (the heart/the King)", "moral self (the conscience/the Judge)", "animal self (the animal soul/the Elephant)", "showing-off self (the self-centric ego/the Showman)", "oppressive self (the oppressive ego/the Dog)", and "deciding self (the free will/the Driver)". Therefore, one needs to know oneSELVES in a holistic manner in order to make ourSELVES happy.
Aydin defines happiness as the fulfillment of the needs and desires of multipleselves in a harmonious way. For instance, the spiritual self (the King) has almost infinite capacity to love. He needs/desires beauty, perfection, and benefits in his lover(s). From his perspective, life is a journey of making attachments to satisfy these needs. Attachments can be made with material and/or immaterial things such as money, property, lovers, friends, nature, and God. The moral self (the Judge) wants fairness and justice in life and would cause moral pleasure if we treat and are treated fairly. He will make us feel moral pain if we participate in unfair acts. The reasoning self (the Wazir) pursues knowledge and receives intellectual pleasure from learning. He performs the role of making rational decisions for the spiritual self (the King) and other-selves such as the animal self (the Elephant) and the moral self (the Judge). However, he has no power to endorse his decision and may be silenced if the animal self is too strong. The animal self is the greedy, animal nature of human beings. He has the capacity for sensual experience through using the five senses. He needs and/or desires many things such as food, drink, sleep, sex, etc. The showing-off self (the Showman) is motivated by acts that gain recognition and fame. He frequently compares his own possessions with those of others. The oppressive self (the Dog) is the power to control and rule others. If he is not constrained by moral and legal codes, he would oppress others for his interests. The deciding self (the Driver) is the free will, which is the ultimate decision-maker (the willpower). He is the one in the driving seat in life. However, he acts under the influence of the other-selves.
The G-donic model perceives happiness as the process of dealing with multiple selves in a harmonious way. In other words, happiness is the byproduct of living according to God's pleasure. It is an overall life satisfaction for the multiple selves while staying on the straight path (sirat al-mustaqeem). In other words, happiness is to drive one's life with strong willpower (the Driver) under the collaborative command of the King (heart), Judge (conscience), and Wazir (mind). It is to drive toward excellence with sincere spiritual, intellectual, and moral intentions and actions. It is to keep the Elephant (animal soul), Dog (anger), and Showman (egoistic self) under the command of the King, Wazir, and Judge.
While the G-donic model provides guidance to nourish heart, mind, and intellect, it also highlights the danger of being a slave to the animal soul, ego, and anger. It warns people that if not trained, the Elephant, Showman, and Dog will dominate the life and urge certain irrational actions despite any objection from the King, Wazir, and the Judge. The Gdonic model provides nourishment for the King who has the capacity for love, compassion and inspiration. It guides people on how to find authentic and lasting love in life for the fulfillment of the King. It discusses the role of loving mates, children, friends and jobs in the pursuit of happiness. The G-donic model notes that the inner Judge (conscience) always makes a judgment about what we do to others. If we treat someone unfairly, the inner Judge causes us to be aware of this injustice and feel guilty for being unfair. If we treat others fairly, we receive spiritual pleasure experienced through the fulfillment of the Judge. The G-donic model presents the food station for the Wazir who is thirsty for knowledge and meaning. Finding meaning in life is very important for the Wazir because as the navigator, he needs to know where to go. Life without meaning is like driving without knowing the destination. The G-donic model also offers a guide on how to keep the animal soul, showman, and dog under control through strong willpower (the Driver). It suggests moderation in consumption and warns about the poisons present in some food. It makes some recommendations for pleasure maximization under constraints of the "law of diminishing marginal utility", "adaption principle", and the "hedonic treadmill".
The happiness function based on the G-donic model captures seven different dimensions of the human experience as represented by seven elements (residents) of human nature. For instance, happiness for the King depends on how one fulfills the needs/desires of love, compassion and inspiration. Love pursues beauty, perfection and benefits. Life for the King in this regard is a journey of making attachments. The number, intensity, and duration of attachments produce spiritual or esthetical pleasures. As the King gains pleasure by making attachments through love, compassion, and inspiration, he also suffers from any detachments that occur. Like the King, each resident of the human vehicle experiences pain and/or pleasure from daily activities. Therefore, we could define happiness as a net result of interaction between subjective well-being for all residents in the matrix.

Comparisons of Hedonic and G-Donic Happiness Models
In the G-donic model, happiness is not a destination; it is a state of being while driving for spiritual, moral, and intellectual excellence. It is the progress made toward excellence on the straight path. According to the Divine guidance, happiness is the byproduct of living according to human nature and fulfilling one's mission. The final end is God's pleasure which leads to salvation in the hereafter. The Qur'an clearly states that God's pleasure is the highest good [28]: "God has promised the believers, both men and women, Gardens through which rivers flow, therein to abide, and blessed dwellings in Gardens of perpetual bliss; and greater (than those) is God's being pleased with them. That indeed is the supreme triumph" (Qur'an, 9:72) [24].
Believers are called to do everything only for God's pleasure. For instance, when rich believers help the poor, they are asked to say the following to them: "We feed you only for God's sake; we desire from you neither recompense nor thanks (we desire only the acceptance of God)" (Qur'an, 76:9) [24]. Believers are also asked to say the following: "My Prayer, and all my (other) acts and forms of devotion and worship, and my living and my dying are for God alone, the Lord of the worlds" (Qur'an, 6:162) [24].
The G-donic model is fundamentally different from the hedonic happiness model. While the former puts God's pleasure as the highest good in the pursuit of happiness, the latter sees self-pleasure as the ultimate purpose. The hedonic model defines happiness as net experienced pleasure over pain while the G-donic model considers happiness as the experienced level of reality. For the G-donic model, happiness is not a function of pain and pleasure. Rather, it is a function of attaining a transcendental dimension. Pain and pleasure experienced through life events are just fluctuations of the happiness level.
The difference between the two happiness models is also due to their understanding of human nature. In the G-donic model, true and lasting happiness can be possible if the needs and desires of all residents are met in a balanced way. In the hedonic model, the elephant, showman, and/or dog are in the driving seat. Indeed, all other-selves work hard to please them. People become only the slave of their desires. They generally pursue their sensual pleasure. They think life is "just" fun. They sacrifice virtue for their instant pleasure if their virtue contradicts their animal desires. The problem is that the elephant and the showman are greedy, and therefore never satisfied. They are also blind to the future, and therefore, they focus on short-term pain and pleasure, rather than the long-term ones. Furthermore, some of their desires could be harmful to other residents. Therefore, pleasing them alone cannot bring anyone happiness [29].
The two models also differ on the need for wealth in the pursuit of happiness. The external means are an absolute necessity for the hedonic model. That is why Adam Smith, the father of modern capitalism, titled his manifesto "The Wealth of Nations". Likewise, John Stuart Mill defined economics strictly based on the generation of material wealth: "Political Economy considers mankind as occupied solely in acquiring and consuming wealth. Under the influence of this desire, it shows mankind accumulating wealth and employing that wealth in the production of other wealth; sanctioning by mutual agreement the institution of property; establishing laws to prevent individuals from encroaching upon the property of others by force or fraud. All these operations, though many of them are really the result of a plurality of motives, are considered by political economy as flowing solely from the desire of wealth" [30].
In the G-donic model, it is necessary to have the basic means to nurture the body and soul. However, it is not necessary to be wealthy even though there is nothing wrong with being so [31]. For that matter, wealth is "preferred indifference" [19]. In other words, for the desired outcome of life, wealth is not necessary because it is just a means. As is stated by the Prophet Mohammed (pbuh), in the end, what really matters are the deeds: "Certainly God looks not at your faces or your wealth; instead, He looks at your heart and your deeds" (Muslim, v. 4: 1987: 34) [28].
The Quran reminds its believers, time and again that this life is a test where they will be tested in choosing between the right and the wrong. Ibn al-Qayyim says, since life is a test and trial, it does not matter whether the questions come in the form of poverty or wealth. As the possession of wealth is not a sign of God's favor, the lack of wealth is also not a sign of His disfavor. In other words, the goal in life is not to be rich, rather it is to live a virtuous and sincere life to earn God's pleasure. According to Ibn al-Qayyim, wealth is preferable, provided that it accompanies thanksgiving to Allah and helps to fulfill one's duties and obligations towards fellow human beings. Likewise, lbn al-Qayyim's student, Ibn Taimiyah, says that "from among the rich and the poor, the most favored creature is he who is most God-fearing and who excels in good deeds; if a rich and a poor person are equal on the basis of this criterion, they are equal in their ranks. This means that without external goods, it is still possible to achieve the highest excellence. Again, this confirms that beyond basic necessities, "external goods" are preferred but not necessary.
As outlined in Table 1 below, the differences between Hedonic and G-donic happiness models could be summarized as follows. First, the hedonic model aims for self-pleasure while the G-donic model aims for a purposeful life to achieve God's pleasure. Self-pleasure is the byproduct of God's pleasure in the G-donic model. Second, the hedonic model encourages higher consumption for greater happiness while the G-donic model promotes moderation as Islam promotes moderation and thankfulness as part of one's relationship with God. Third, the hedonic model takes self-interest and rationality as a guide while the G-donic model value other-regarding and pro-social behavior as virtuous based on Divine guidance. Fourth, the Hedonic model considers external prosperity as a necessary means for happiness, while the G-donic model promises happiness even without external prosperity. Finally, the Hedonic model considers everything including education as means for prosperity and pleasure while the G-donic model perceives education as means for truth, virtue, and sincerity once one becomes aware of transcendental reality.

Comparison of Eudemonic, G-Donic and Higher-Order G-Donic Approaches
Eudemonic and G-donic models overlap greatly in terms of putting emphasis on virtue and excellence. Both Eudemonic and G-donic models define flourished, fulfilled, and virtuous life as a happy one. They liken humans to seeds and define happiness as the flourishing of that seed toward its end. As the ultimate end for an apple seed is to be an apple tree with many fruits, the ultimate end for each human being is also to be flourished toward their own fruit. However, the difference between the two models lies in their understanding of a flourished, fulfilled, and virtuous life.
Aristotle is considered to be the father of eudemonic happiness. In his famous book, Nicomachean Ethics, he asks the following question: what is worthy to pursue in life as the final end? Aristotle used an analogy to come up with an answer. He began with an example of a craftsman who works for an end: "Every craft [technē] and every line of inquiry [methodos], and likewise every action [praxis] and decision [proairesis], seems to seek some good; that is why some people were right to describe the good as what everything seeks" [4] (p. 1094a). In other words, we all aim for some ends, which are categorized as intermediate or final ends. We value intermediate ends as a means to reach the final ends. For Aristotle, the final end or final good is the one that is desired for itself, not as means for other ends. Aristotle argues that happiness is the final end because it is desired for itself alone. Aristotle defines happiness as a virtue, not sensual pleasure, even though it comes with pleasure. In his view, happiness is not virtue as ideas but as actions. Thus, happiness is possible through virtuous actions in life. "We are neither called good nor called bad, nor are we praised or blamed, insofar as we are simply capable of feelings. Further, while we have capacities by nature, we do not become good or bad by nature" [4] (p. 1106a). We become happy if we engage in an "activity in accord with virtue" [4] (p. 1098b). Thus, eudemonic happiness is to excel through virtuous actions to reach one's potential.
The G-donic approach bears similarity with the eudemonic approach in giving importance to virtue and telos. There are, however, fundamental differences. First, the scope of the eudemonic approach to happiness is as wide as the scope of the term virtue. This could embody a set of broadly defined common virtues or narrowly defined idiosyncratic commitments. These may change from individual to individual and society to society. G-donic virtues are, however, more comprehensive in the sense that they are defined to achieve a goal that is common between a large group of individuals through a common source, divine in this case. Thus, even though both models consider moderation (golden mean) as a way of defining virtuous behaviors, they differ in terms of how they define moderation. Second, eudemonic virtues may see happiness as an end, whereas the G-donic approach sees seeking the pleasure of God as the end and worldly happiness as a byproduct of commitment to the end. Third, in the G-donic model, virtue is not based on consequences in this world alone. It is based on consequences in both this world and the hereafter. Unlike the G-donic approach, the eudemonic approach may not necessarily associate with the concept of the hereafter, which makes it prone to a commitment problem. The commitment problem arises when individuals compromise their commitment to virtues according to their convenience, especially when tested to limits. If life is limited to this world, it is hard to embrace certain values at the cost of worldly benefits or even life itself. It is, therefore, best to think of the G-donic happiness as a higher-order eudemonic approach to happiness. It is of a higher order because religion gives sanctity to a well-defined set of virtues that underlie one's purpose in life, unlike virtues in general which may change from one individual to another in terms of its scope and commitment of the individual. Table 2 below provides key differences between eudemonic and G-donic happiness. It is also useful to differentiate between higher-order G-donic from G-donic itself. Whereas the G-donic approach accommodates cases where individuals show their commitment to God to please Him with expectations about reward in this world and the hereafter, true commitment to please God should be independent of such expectations. We refer to this category as the higher-order G-donic where one becomes selfless in that nothing matters more than pleasing God. Quranic ontology suggests that men should strive to achieve this ideal state. This is when they achieve the highest level of happiness in this world and in the hereafter.

Determinants of Subjective Wellbeing in Three Happiness Models
In a book titled 3D of Happiness, Aydin [22] categorizes subjective wellbeing (SWB) in three distinctive models: Hedonic (pleasure-seeking), Eudemonic (earthly meaning), and G-donic (spiritual meaning). In the hedonic SWB model, the objective is to maximize utility or pleasure through H:having (possession), D:doing (pleasant experience), or B:being (position). By having, it is meant "possessing something to be happy about, such as having nice clothes, a fancy house, a great car, etc. It is all about possessing something as a means to be happy or happier. By doing, it is meant "experiencing, such as traveling, watching, playing. Doing is all about entertainment and fun activities. Having is to focus on possession, while doing refers mainly to sheer experience. By being, it is meant "position or status such as being a respected teacher, engineer, scientist, etc. It is all about gaining a certain status or respect in the eyes of others. Thus, seeking happiness through the hedonic model is one dimensional which is defined as:

Hedonic, Eudemonic and G-Donic Models: An Illustration through Utility Function
As should be obvious from the above characterization, the multi-dimensional human nature model can be used to study a wide variety of interactions between the players in a variety of environments. In this section, we will limit our discussion to models of happiness that elicit happiness through utility functions. In the following, we will try to use the utility approach to highlight key differences between hedonic and eudemonic approaches to happiness and discuss the implications of moving from the eudemonic to G-donic approach. Our main purpose is to demonstrate that deviation from hedonic preferences and commitment to a purpose in life result in greater happiness.
Economic theories typically assume individuals to be sordidly selfish. Standard utility functions, therefore, define utility in terms of an individual's own consumption. A relatively recent trend in economics is to model individuals as other-regarding, mainly due to evidence from laboratory experiments where researchers found robust evidence in favor of non-selfish or other-regarding behavior. There is a wide variety of models which modify the standard utility functions to capture different aspects of the other-regarding behavior [32][33][34][35][36][37][38]. The most frequently used model, which is useful for our purpose here as well, is the Fehr and Schmidt [39] model of equality aversion. The Fehr and Schmidt utility function, with two individuals, is given below. (for i = 1, and 2) where U(X i ) is the selfish utility of individual i ( = 1, 2) from own consumption. Fehr and Schmidt use a linear utility function for simplicity where U(X i ) = X i . For tractability, let us replace X i with M (referring to my consumption) and X j with Y (referring to your consumption). We can re-write "My" utility function as follows.
The first term on the right-hand side is selfish utility from own consumption. The second term is disutility from advantageous inequality (utility gap from differences in consumptions advantageous to me), and the third term is disutility from disadvantageous inequality (utility gap from differences in consumptions disadvantageous to me). The Fehr and Schmidt [39] model, therefore, assumes that individuals are inequality averse. Thus, individuals derive disutility from the distribution of income whenever income is not equally distributed in society. β and α are the preference parameters.
This utility function is depicted in Figure 1. The figure normalizes resources to 1 dollar, which is distributed between M and Y. For simplicity, let us assume "I" have all the resources and need to decide whether to keep all or share it with "You".
My selfish utility is given by the line OC. My social (other-regarding) utility for different values of the preference parameter β is given by ABD, ABE and ABF. Let us note a couple of important points before we proceed to further analysis.
My disutility from disadvantageous inequality (M < Y) reduces my overall utility. This is essentially the envy effect associated with disadvantageous inequality where a comparison with you reduces my utility.
Note that when β < 0.5, the solution is exactly the same as the selfish utility (i.e., β = 0). Thus, when preference against advantageous equality is not too strong, the outcome is no different from that of a selfish economy. This also means that observing a selfish solution in the real world does not necessarily mean that individuals are sordidly selfish.
When social preferences are strong (β > 0.5), my utility, represented by ABF, is maximum when I evenly share resources with you as M = Y = 0.5. My selfish utility is given by the line OC. My social (other-regarding) utility for different values of the preference parameter β is given by ABD, ABE and ABF. Let us note a couple of important points before we proceed to further analysis.
My disutility from disadvantageous inequality (M < Y) reduces my overall utility. This is essentially the envy effect associated with disadvantageous inequality where a comparison with you reduces my utility.
Note that when β < 0.5, the solution is exactly the same as the selfish utility (i.e., β = 0). Thus, when preference against advantageous equality is not too strong, the outcome is no different from that of a selfish economy. This also means that observing a selfish solution in the real world does not necessarily mean that individuals are sordidly selfish.
When social preferences are strong (β > 0.5), my utility, represented by ABF, is maximum when I evenly share resources with you as M = Y = 0.5.
Khan and Ahmed [40] argue that individuals are inequity averse in general and that equality aversion holds under restricted conditions. They further argue that an individual's idea of equitable distribution is state-dependent where the nature of the state is determined by psychological and structural parameters. Psychological parameters primarily include tendencies that are either hard-wired in human nature, such as self-serving bias, or a part of one's cultural/religious affiliations; one's real-life experiences (including experience in the laboratory); one's perception about the behavior of others (kind, selfish etc.); and one's perception about his/her socio-economic status relative to those of others. The "structural parameters" mainly related to the design of the experiment (such as how are different roles and property rights allocated, information about the socio-economic status of players, the wording of the experiment, and role of the experimenter, etc.). Khan and Ahmed [40]  Notice that the extended model reduces to the Fehr and Schmidt [39] model when e = 1. When e = 2, "I" believe that equitable distribution requires that my income is twice as much as yours, and so on. Again, suppose there is one dollar in the economy which "I" Khan and Ahmed [40] argue that individuals are inequity averse in general and that equality aversion holds under restricted conditions. They further argue that an individual's idea of equitable distribution is state-dependent where the nature of the state is determined by psychological and structural parameters. Psychological parameters primarily include tendencies that are either hard-wired in human nature, such as self-serving bias, or a part of one's cultural/religious affiliations; one's real-life experiences (including experience in the laboratory); one's perception about the behavior of others (kind, selfish etc.); and one's perception about his/her socio-economic status relative to those of others. The "structural parameters" mainly related to the design of the experiment (such as how are different roles and property rights allocated, information about the socio-economic status of players, the wording of the experiment, and role of the experimenter, etc.). Khan and Ahmed [40]  Notice that the extended model reduces to the Fehr and Schmidt [39] model when e = 1. When e = 2, "I" believe that equitable distribution requires that my income is twice as much as yours, and so on. Again, suppose there is one dollar in the economy which "I" need to distribute between me and you. Figure 2 plots the extended utility function where β 0 = 1/(1 + e).
As obvious from the figure, I will transfer Y = 1/(1 + e) to you only if β > β 0 (when the disutility from inequity is strong). However, notice that this is a weaker requirement than Fehr and Schmidt [39]. β 0 is 0.5 in the Fehr and Schmidt model and M = Y = 0.5 when β > 0.5 (otherwise M = 1 and Y = 0). Unlike the Fehr and Schmidt model when 1/(1 + e) < β < 0.5, Y = 1/(1 + e) which is greater than 0. Thus, I will still transfer some amount even when β < 0.5. This is more realistic as it allows for a solution in the interior of no-split and equal-split of resources. Notice that dM/de > 0 and dY/de < 0 implying that the proportion of resources that I keep for myself goes up as my equity bias changes in my favor and vice versa. need to distribute between me and you. Figure 2 plots the extended utility function where β0 = 1/(1 + e). As obvious from the figure, I will transfer Y = 1/(1 + e) to you only if β > β0 (when the disutility from inequity is strong). However, notice that this is a weaker requirement than Fehr and Schmidt [39]. β0 is 0.5 in the Fehr and Schmidt model and M = Y = 0.5 when β > 0.5 (otherwise M = 1 and Y = 0). Unlike the Fehr and Schmidt model when 1/(1 + e) < β < 0.5, Y = 1/(1 + e) which is greater than 0. Thus, I will still transfer some amount even when β < 0.5. This is more realistic as it allows for a solution in the interior of no-split and equalsplit of resources. Notice that dM/de > 0 and dY/de < 0 implying that the proportion of resources that I keep for myself goes up as my equity bias changes in my favor and vice versa.
An important aspect missing from the Khan and Ahmed [40] extension is the effect other-regarding behavior might have on the level of the utility. The above specification assumes that I derive the same level of selfish utility from a dollar irrespective of whether or not I care about society. This is naturally very unlikely to be the case as "goodness" induces greater satisfaction from existing resources. We, therefore, need to allow for interaction between the social utility and selfish utility. This could be done in a number of ways. In order to demonstrate the importance of this misspecification, let us introduce a relatively straightforward extension of the model as follows (assuming α = 0 for simplicity). This specification admits a variety of interesting behaviors. When β = 0, T = 1 and the function reduces to the standard selfish utility function. As β increases, I derive more "selfish" utility from each dollar. This changes the level of utility derived from the same resources. This is tantamount to postulating that the good act of caring for others (inspired by meaning in life) increases the efficiency with which a unit of consumption is translated into utility. This "technological" improvement is nature's way of reciprocating good actions through increasing the efficiency with which a dollar is converted into utility. Figure 3 shows this effect graphically. An important aspect missing from the Khan and Ahmed [40] extension is the effect other-regarding behavior might have on the level of the utility. The above specification assumes that I derive the same level of selfish utility from a dollar irrespective of whether or not I care about society. This is naturally very unlikely to be the case as "goodness" induces greater satisfaction from existing resources. We, therefore, need to allow for interaction between the social utility and selfish utility. This could be done in a number of ways. In order to demonstrate the importance of this misspecification, let us introduce a relatively straightforward extension of the model as follows (assuming α = 0 for simplicity). This specification admits a variety of interesting behaviors. When β = 0, T = 1 and the function reduces to the standard selfish utility function. As β increases, I derive more "selfish" utility from each dollar. This changes the level of utility derived from the same resources. This is tantamount to postulating that the good act of caring for others (inspired by meaning in life) increases the efficiency with which a unit of consumption is translated into utility. This "technological" improvement is nature's way of reciprocating good actions through increasing the efficiency with which a dollar is converted into utility. Figure 3 shows this effect graphically.
An increase in the intensity of social preferences (increase in β) further induces altruism and result in a greater transfer of resources to others (as shown by a leftward shift in the kink-maximum of social utility as β increases). This is because T increases as β increases, which widens the feeling associated with the inequity gap (AM-eY).
Going back to the central theme of the paper, happiness is ge›nerally related to utility. The selfish utility function (or social utility with envy associated with disadvantageous inequity) in general represents hedonic happiness. Since the Eudemonic approach to happiness brings morality into the picture, the social utility function which models other-regarding behavior as above is an example of Eudemonic happiness. The G-donic model further strengthens the social preference parameters and result in greater utility and equitability.  An increase in the intensity of social preferences (increase in β) further induces altruism and result in a greater transfer of resources to others (as shown by a leftward shift in the kink-maximum of social utility as β increases). This is because T increases as β increases, which widens the feeling associated with the inequity gap (AM-eY).
Going back to the central theme of the paper, happiness is ge›nerally related to utility. The selfish utility function (or social utility with envy associated with disadvantageous inequity) in general represents hedonic happiness. Since the Eudemonic approach to happiness brings morality into the picture, the social utility function which models other-regarding behavior as above is an example of Eudemonic happiness. The G-donic model further strengthens the social preference parameters and result in greater utility and equitability.
In terms of the comprehensive human nature model, hedonic happiness corresponds to the case when the Driver (willpower) surrenders to the Elephant (animal soul), Dog (anger), and Showman (egoistic self). Resources in this case are the least efficient in terms of generating happiness. This induces greed and a quest for more and more resources and converts men into a consumption machine. Eudemonic happiness triggers when the Driver collaborates with the King (heart), Judge (conscience), and Wazir (mind) when making choices. This collaboration induces them to evaluate the consistency of their choices with their purpose in life. Individuals, in this case, substitute hedonic pleasure with eudemonic rewards (the pleasure from doing the right thing which also increases the efficiency with which an individual's spiritual self converts resources into utility). The greater the commitment is, the greater are the eudemonic rewards. This, in turn, results in greater happiness. Since the meaning and purpose of life is wider than in the simple eudemonic approach, the degree of substitutions between hedonic pleasure and eudemonic rewards is greater, which results in greater happiness.
It is important to highlight two important results before closing this section. As individuals become more pro-social, their happiness increases. This, consistent with what is proposed in this model, recommends an alternative approach to happiness; the spiritual approach to promoting happiness. Most existing approaches to happiness focuses on material resources and ignores the technology or mechanism involved in converting physical resources to happiness [41]. This resources-to-happiness conversion mechanism is spiritual in nature and cannot be served without promoting morality. This In terms of the comprehensive human nature model, hedonic happiness corresponds to the case when the Driver (willpower) surrenders to the Elephant (animal soul), Dog (anger), and Showman (egoistic self). Resources in this case are the least efficient in terms of generating happiness. This induces greed and a quest for more and more resources and converts men into a consumption machine. Eudemonic happiness triggers when the Driver collaborates with the King (heart), Judge (conscience), and Wazir (mind) when making choices. This collaboration induces them to evaluate the consistency of their choices with their purpose in life. Individuals, in this case, substitute hedonic pleasure with eudemonic rewards (the pleasure from doing the right thing which also increases the efficiency with which an individual's spiritual self converts resources into utility). The greater the commitment is, the greater are the eudemonic rewards. This, in turn, results in greater happiness. Since the meaning and purpose of life is wider than in the simple eudemonic approach, the degree of substitutions between hedonic pleasure and eudemonic rewards is greater, which results in greater happiness.
It is important to highlight two important results before closing this section. As individuals become more pro-social, their happiness increases. This, consistent with what is proposed in this model, recommends an alternative approach to happiness; the spiritual approach to promoting happiness. Most existing approaches to happiness focuses on material resources and ignores the technology or mechanism involved in converting physical resources to happiness [41]. This resources-to-happiness conversion mechanism is spiritual in nature and cannot be served without promoting morality. This also implies that resources and spirituality are substitutes as for as happiness is concerned, and a reasonable approach to happiness should seek an optimal mix of both. Islam refers to this optimal mix as "moderation".
Unlike popular convention, deviation from hedonic pleasure does not result in lower happiness. In fact, as shown above, it results in an increase in overall happiness. The loss in hedonic pleasure is more than compensated by the eudemonic reward which increases utility.

Testable Hypotheses for G-Donic Happiness and Suggested Studies
We suggest using existing psychometric evaluation for hedonic and eudemonic models along designing a new survey to test the following hypotheses in a comparative empirical study: Hypothesis 1. People who follow the G-donic happiness model are happier than those who follow the hedonic happiness model Hypothesis 2. People who follow the G-donic happiness model are happier than those who follow the eudemonic happiness model Hypothesis 3. People who follow the G-donic happiness model reach a higher level of happiness even if they are deprived of material means.
In the literature, one can find well-established questionnaires to measure Hedonic and Eudemonic happiness models [42]. We propose a questionnaire that might help with empirically testing predictions of the G-donic Model.
In recent years, researchers have come to a better appreciation of multidisciplinary study to understand human experience due to the complexity of human nature [43]. We observed increasing collaboration between psychologists, economists, and neuroscientists [44]. They have realized that only by combining the mathematical rigor and behavioral precision of economics with the biological inferences drawn from neuroscience can behavior be understood. Particularly, the use of functional imaging (fMRI) has allowed for the measurement of brain activation associated with discrete cognitive experiences such as decision making and reward evaluation. fMRI is a great tool for observing brain activation in response to certain stimulation such as sounds, visuals, touching, even drinking.
In addition to an empirical study, we suggest testing the three happiness models through an experimental study using fMRI. Subjects could be exposed to certain stimuli for pleasure such as watching, contemplating, listening, reading, etc. A functional model of brain activity will be defined and correlated to certain experiences. Such a study will likely reveal brain activity for sensual, intellectual, and spiritual pleasures within the three-dimensional happiness model.

Conclusions
In this paper, we discuss happiness from a spiritual perspective, mainly focusing on Islamic spirituality. We argue that a great majority of the world population has religious affiliations, and it is important to understand happiness from a spiritual perspective. We argue that belief in God and belief in the hereafter play an important role in shaping the mindset of believers. They see this life as a test where their commitment to divine guidance in all aspects of life is tested. They derive happiness by living a life that pleases God. We refer to this approach as the G-donic approach to happiness, which has fundamental differences with the hedonic and eudemonic approaches. The G-donic approach identifies the importance of the spiritual self and argues that it embodies the technology which converts physical resources to happiness. Using Islam as a case study, we argue that Islam identifies living a life according to one's religious commitment as the true source of contentment of one's heart and happiness. The key to happiness is not about living in a huge palace and owning great material possessions, rather, it is about moving beyond the phenomenal dimension and experiencing transcendental reality. Islam takes an active approach in helping its believer remember their commitment as Muslims pray five times a day which keeps them reminded about their religious obligations. They are also given detailed guidance in all aspects of life to be ethical in their actions and dealing. This ranges from respecting the rights of and caring for others to avoid engaging in certain types of financial transactions (such as staying away from giving or charging interest) and avoiding conspicuous consumption as a religious norm.
The G-donic approach contends that resources and spirituality are substitutes, as well as complements, and a reasonable approach to happiness should seek an optimal mix of both. Unlike popular convention, this deviation from hedonic pleasure does not result in lower happiness. In fact, we show that it results in an overall increase in happiness as any loss in hedonic pleasure is more than compensated by eudemonic reward which increases utility.
We understand that our work could be extended in many useful dimensions to highlight the importance of the G-donic preferences for individuals, as well as societies. Indeed, a recent paper by Khan [45] replaces the selfish agent with agents having the G-donic preferences and summarizes results in a theorem called the third fundamental theorem of welfare economics. The theorem states that "when selfish agents are replaced with social agents, market outcomes are Pareto optimal, equitable, and unique". The new theorem holds under conditions where the first two fundamental theorems of welfare economics fail and demonstrates that a Walrasian equilibrium is more likely to exist when selfish preferences are non-convex. This is an important result that has widespread implications. This, along with our analysis in this paper, stresses the need for theoretical and empirical studies to explore the dynamics and determinants of preferences that deviates from the standard hedonic models which might provide guidance for an alternative way of happiness through lower and sustainable consumption. We are happy to report emerging academic studies dealing with multi-dimensions of subjective wellbeing. [43,46] Finally, it is important to note that G-donic happiness might not be limited to Muslims. With certain modifications, it might be applicable to other religions as well. For instance, a famous 13th-century Christian theologian, Thomas Aquinas, did explore happiness in depth. He argues that even though perfect happiness is only possible in the hereafter, imperfect happiness on the earth is possible through God.