In Part II of Summa Theologica, Aquinas provides answer to the question of what human happiness is, and whether it can be obtained in this life. Aquinas contents that as long as man desires and seeks something in this life, he remains unhappy. Man cannot attain perfect happiness because he is incapable of seeing God ( Divine Essence ) in this life. Nothing except the contemplation of the Divine Essence can bring happiness.
No worldly or material good, such as fame, honor, or glory can bring happiness, as they prove to be a part of happiness itself. A state of happiness can exist only when the will no longer seeks anything. Since the will naturally seeks the Divine Essence, it will continue to seek, and thus to be unhappy, until one finds it in death. This puts Aquinas in conflict with Aristotle, who believed complete happiness is attainable in this life as a life lived “in accord with virtue and focused on the contemplation of scientific and philosophical truths.”