Recently I discovered two ancient philosophy papers from the 1970s (by Aryeh Kosman and Myles Burnyeat) drawing a distinction between knowledge and understanding. As far as I can tell, Kosman was the first to propose that the Greek word epistēmē is best translated as understanding, and that in fact it means understanding how to explain what you know, in other words understanding why the thing you know is the way it is.
Without delving into their interpretations of Aristotle's Posterior Analytics, I must say that this distinction strikes a chord with me. Consider a simple example: we all know that trees shed their leaves in autumn, at least in certain parts of the world. But it's an entirely different matter to understand and explain why that is the case, since doing so requires an understanding of all the botanical, environmental, chemical (etc.) factors responsible for the fall of the leaves.
Now extend this model to something much more complicated: say, the role of self-knowledge in human fulfillment. Ever since the saying "Know Thyself" was first inscribed on the walls of the temple at Delphi 2500+ years ago, everyone has known that the phrase contains great wisdom. Yet it's the task of a lifetime to deeply understand those two little words and integrate them with everything you know about psychological development, individual maturation, the virtues, human relationships, and so on - both in theory and in your own practice of living.
Knowledge is relatively easy; understanding is really, really hard.
(Cross-posted at philosopher.coach.)
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