G. Reale, A History of Ancient Philosophy: The Systems of the Hellenistic Age, trans. John R. Catan (Albany: State University of New York Press, 1985) 60.
There is nothing to which Plato, right down to the end of his life, was more passionately opposed than the statement that the soul can know that is just without being just.
According to Plato (fifth-fourth century B.C.E.), the person who truly knows the good will want to do the good. This makes a certain amount of sense. If I truly know the good, then I recognize its beauty and the positive effects that it brings, which should inspire me to do it.
When I took a philosophy class at DePauw University, however, there were students who disagreed with Plato. “When I smoke a lot and cough shit up, I know that’s not good for me!,” a student exclaimed. “Yet, I keep on smoking.” If my memory serves me correctly, the professor brought Aristotle into the discussion, asserting that there’s such a thing as weakness of the will. In certain philosophical scenarios, one can know the good but be too weak to do it.
What are some biblical teachings on this topic? I suppose we get a mixed bag! Here are three teachings that come to my mind:
1. Knowledge of the LORD leads to ethical behavior. Isaiah 11:9 affirms, “They will not hurt or destroy on all my holy mountain; for the earth will be full of the knowledge of the LORD as the waters cover the sea” (NRSV).
2. One can know the good and even delight in it, yet there’s a law within that person that inclines him to evil (Romans 7-8).
3. One can fall away from the faith after tasting the goodness of God. Hebrews 6:4-6: “For it is impossible to restore again to repentance those who have once been enlightened, and have tasted the heavenly gift, and have shared in the Holy Spirit, and have tasted the goodness of the word of God and the powers of the age to come, and then have fallen away, since on their own they are crucifying again the Son of God and are holding him up to contempt.”
I’d like to think that knowing the good and why it is good would inspire a person to do the good. But maybe weakness of the will can inhibit us, or a short-sighted desire for our own self-interest.