What is the aim of human endeavor? Is ignorance truly bliss? Gordon H. Clark provides a peek into the happiness-centric ethical philosophies of Aristotle and Augustine (emphasis in bold is my own):
“Happiness” (eudamonia, from which we derive eudaemonism) is the term Aristotle used to designate the goal of life. It is an end in itself, never a means to anything else. “Honor, pleasure, intelligence, and all forms of virtue, we choose both for their own sakes, … and we also choose them for the sake of happiness. … But no one chooses happiness for the sake of honor or pleasure, nor as a means to anything else at all” (Nicomachean Ethics, I, vii, 1097b1-6).
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Augustine’s ethics was also eudaemonism. The good life is one of happiness (beatitudo, beatitas; both terms coined by Cicero). All men desire happiness (De Trinitate, X, v, 7). “No one lives as he wishes unless he is happy” (De Civitas Dei, XIV, 25). Now Augustine would not disparage virtues such as courage and temperance; nor would he belittle rational thought. In fact, no one can be happy without knowledge of the truth. In this there is similarity to Aristotle. But Augustine replaces Aristotle’s secularism with Christian content. God is truth and to know God is wisdom. Therefore the happiness Augustine recommends becomes blessedness or beatitude.
More explicitly: wisdom is not the knowledge of some heathen god, nor even of, say, Spinoza’s first principle. To have wisdom is to have Christ. Christ is the truth; Christ is the wisdom of God.
One reason for making truth the aim of our endeavors is that if we love what can be lost, we cannot be happy. But God, Christ, and truth are immutable, and if we have this, our blessedness is permanent (“Happiness,” Essays on Ethics and Politics, pp. 109-110; originally published in Baker’s Dictionary of Christian Ethics, Carl F.H. Henry, editor. Grand Rapids, Michigan: Baker Book House, 1973, pp. 281-282.).