What gives human life meaning, and how should one act in the world once one realizes this meaning?
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There are a number of philosophical schools of thought concerning what gives life meaning. The deontological school of thought suggests that the purpose of life is to fulfill one's duty or obligation. Duties are prescribed by social status: husband, wife, brother, citizen, employer and employee each have distinct obligations. The existential school of thought suggests that life has no inherent meaning, and that individuals must create meaning through their own action. Existentialists argue that there is no cosmic, divine, or universal meaning to human life. We create meaning by acting virtuously, creating beauty, and maintaining our integrity. When one does realize the meaning of life, one should act in such a way as to actualize that meaning and fulfill one's purpose.
The meaning of life and acting upon life’s perceived purpose is a question pondered across many disciplines including philosophy, psychology, religion, art, science, and literature. All of these disciplines answer pertinent questions relative to life and its meaning quite differently. Yet, one unifying existential concept that many disciplines seem to share is contemplating the existence of a soul. One’s life meaning is determined and directed by the desires of the soul. Life’s course is plotted by navigating the conflicts between satisfying the soul’s desires vs. meeting the world’s demands. One short answer to questioning the meaning of life might be: It’s all relative. A few links below offer further insights.