Understanding Happiness by Thomas Aquinas

In Aquinas’ Summa Theologica, he defines man to be made in the image of God, man’s end to be perfect happiness, which may only be attained by seeing God, and asserts the Divine law’s role in the attainment of perfect happiness. Much like Aristotle, Aquinas believes a man is the composition of the body and the soul, the soul is divided into the rational and irrational, and the rational part of the soul is the most essential part to man’s happiness. However, for Aquinas, this is an incomplete definition of man. Man is created in the image of God, which redefines the rational part of the soul. In the beginning of the First Part of the Second Part, he says, “Man is said to be made to God's image, in so far as the image implies an intelligent being endowed with free-will and self-movement.”

Since man has been created in the image of God, he is endowed intellect, so he may have the capacity to know God, and free will, so he may be able to love God. These two distinct attributes of the rational part of the soul define human nature, and also human actions. He wrote, “Now man is master of his actions through his reason and will; whence, too, the free-will is defined as ‘the faculty and will of reason.’ Therefore those actions are properly called human which proceed from a deliberate will. And if any other actions are found in man, they can be called actions "of a man," but not properly "human" actions, since they are not proper to man as man.” (1.1) He states that if the will of a man is an essential component to what makes his actions uniquely human actions, then all human acts are aimed toward a good, because the intellect guides the will toward an end. In summary, man is created in the image of God and possesses intellect and free will, and all human actions use intellect and free will.

Aquinas believes that man’s end is happiness, specifically perfect happiness. Again, much like Aristotle, happiness pertains to the rational part of the soul. However, the philosophies and the idea of supreme happiness for Aristotle fell short for Aquinas, and he labeled Aristotle’s happiness as “imperfect happiness”, or happiness that pertains to life on earth. He wrote, “But imperfect happiness, such as can be had here, consists first and principally in contemplation, but secondarily, in an operation of the practical intellect directing human actions and passions.” (3.6) In contrast, perfect happiness consists only of contemplation, whereas imperfect happiness relates to speculative practical intellect on earth. Aquinas stated, “Nevertheless the operations of the senses can belong to happiness, both antecedently and consequently: antecedently, in respect of imperfect happiness, such as can be had in this life, since the operation of the intellect demands a previous operation of the sense; consequently, in that perfect happiness which we await in heaven; because at the resurrection, ‘from the very happiness of the soul.’” (3.3). Even though man is capable of achieving happiness on earth, that happiness is imperfect or incomplete. Perfect happiness, the true end of man, is something that only may be achieved in heaven by seeing God, the beatific vision. Aquinas wrote, “Final and perfect happiness can consist in nothing else than the vision of the Divine Essence.” (3.8). Nothing on earth will ever make a man completely and perfectly happy; seeing God is man’s perfect end. Since man’s end is God, it is necessary for man to have a way to be directed to his end.

Aquinas has several different kinds of law. The first kind of law is eternal law. Aquinas describes eternal law when he wrote, “Now it is evident, granted that the world is ruled by Divine Providence, that the whole community of the universe is governed by Divine Reason. Wherefore the very Idea of the government of things in God the Ruler of the universe, has the nature of a law. And since the Divine Reason's conception of things is not subject to time but is eternal, according to Proverbs 8:23, therefore it is that this kind of law must be called eternal.” (91.1) The eternal law dictates all other law, because it is God’s providence. Aquinas then defines the natural law, which is the rational creature’s participation in the eternal law (91.2). From the natural law, we get the human law, which Aquinas defines, “Accordingly we conclude that just as, in the speculative reason, from naturally known indemonstrable principles, we draw the conclusions of the various sciences, the knowledge of which is not imparted to us by nature, but acquired by the efforts of reason, so too it is from the precepts of the natural law, as from general and indemonstrable principles, that the human reason needs to proceed to the more particular determination of certain matters. These particular determinations, devised by human reason, are called human laws.” (91.3). The human law is the law man practices in government. It is derived from the natural law for specific instances that require more particular guidance. Both the natural and human law directs man toward his natural faculty, which is imperfect earthly happiness. However, Aquinas has established that the end of man is perfect happiness, which necessitates a Divine law, so that man might be directed to his end of seeing God. (91.4) The Divine law is the Bible, or “that which is enacted by God and made known to man through revelation.” (Slater). Therefore, all law directs man toward an end. However, natural and human law only directs man to imperfect happiness, whereas the Divine law directs man to perfect and complete happiness, or more specifically God.

Aquinas defines man to be made in the image of God, man’s end to be perfect happiness, which may only be attained by seeing God, and asserts the Divine law’s role in the attainment of perfect happiness. As mentioned above, Aquinas’s philosophy is the completion of the Ancient thought. Aristotle was only able to reason to a first cause, since he only considered happiness which may be attained on earth by the activity of the rational part of the soul. Aquinas, however, acknowledged the first cause, which redefined the entire definition of man, his end, and the role of the law.