Islam identifies happiness with a moral attainment as well as a fulfillment of human capacities— a self-fulfillment helmed by the faculty of understanding, of distinguishing between right and wrong.
The Qur’an asserts that human success and prosperity depends on himself, “truly he succeeds that purifies the Soul, and he fails that corrupts it”(Al-Shams (91): 9-10).
There can be no question of any attainment or progress unless the purity of the self is preserved and developed.
Corrupt soul is the one which is estranged from its reality, and has lost its integrity. A well-known Tradition expresses that, “He who knows himself best, knows his Lord best.” By becoming fully ourselves, hence, we realize goodness as well.
Therefore, the knowledge of the soul as well as its powers and properties is both the precondition of causing the soul to grow in purity as well as the prelude to the ultimate happiness. Such knowledge is fundamental to developing one’s highest potentialities.
In his analysis of the human soul, religious thinkers like al-Ghazzali distinguish between an aspect which is inclined to evil deeds and another aspect which is predisposed to praiseworthy acts.
In Islamic psychology, the former is called the carnal or animal soul (al-nafs al-hayawaniyyah) and the latter the rational soul (al-nafs al-natiqah); while in Western psychology, the former is called desire (or sentience) and the latter reason (or rationality).
To the former, indeed, belong the powers of motion, desire and perception, while the latter possesses the knowing and acting powers, that is to say, the theoretical and practical—or the cognitive and active—faculties (al-‘aql al-‘alimah and al-‘aql al-‘amilah). The active power is a faculty which moves the body of man to perform particular actions, involving reflection and deliberation as directed by the cognitive powers.
To the extent that the powers of the carnal soul are controlled by the active power of the rational soul, virtuous traits arise in the soul.
On the contrary, to the extent that the latter power is vanquished by the former powers, vicious traits arise.
As mentioned in Professor Dr Syed Muhammad Naquib al-Attas’s The Meaning and Experience of Happiness in Islam, insofar as the rational soul governs and manages the human body, it induces ethical behaviour in man involving the recognition of vices and virtues.
Rational soul demands nothing which is opposed to human nature (fitrah), while virtue means nothing but acting according the “laws” of our own nature (fitrah) which has been created by God.
That is due to the fact that the ultimate source of happiness is God, who imparts it to us through diverse means.
Hence, erudite scholars such as al-Ghazzali argue that man’s sole duty consists in keeping our soul in constant readiness to receive the divine illuminations, by cleansing it and keeping it pure and unadulterated, from hatred, envy, pride, greed, and the like.
The Prophet Muhammad says that, “Your Lord has reserved for you in your lifetime certain breezes; expose yourselves to them.”
The Prophet also relates in a hadith qudsi that, God says that “Whoever comes closer to Me by one span, I will come closer to him by one yard, and whoever comes to Me walking, I will come to him running.”
All these traditions imply that the obstruction of knowledge and happiness is never God’s, but rather man’s.
The degrees of proximity to God are innumerable and upon these degrees depend the stations of human beings, the highest degree being that of the prophet to whom are revealed all the realities. In short, this proximity to Allah is the highest point that the soul can attain.
According to al-Ghazzali, there are three principal powers of the soul: the rational, the irascible and the concupiscent.
When these powers have been rightly ordered in the desired manner and to the desired degree, and the powers of anger and appetite subordinated to the rational, moral justice (al-‘adalah) arises.
This justice is the foundation on which have been established not only the heaven and the earth but also the path of religious piety and praiseworthy moral rectitude.
In contemporary intellectual idioms, the above-mentioned is referred to as the realization of the true self, whose interests extend to one’s family members, friends, neighbours, community, and all mankind.