The mind itself is the medium of all knowledge, and the quality of that knowledge depends upon the quality of the mind. A dull mind will produce dull knowledge; a penetrating mind will penetrate to the heart of things.
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The mind of a thoroughly well-informed man is a dreadful thing. It is like a bazaar overcrowded with cheap wares, all of them perhaps useful or insignificant, jostling against each other and preventing the customer from getting what he really needs.
Aldous Huxley — On the Margin: Notes and Essays
The mind of a thoroughly well-informed man is a dreadful thing. It is like a bazaar encumbered with rich but cumbersome and never to be used articles.
Oscar Wilde — The Importance of Being Earnest
The best investment is in yourself, but the second-best is often in businesses where you can understand what they do and where they're going better than the market does.
Charlie Munger — Berkshire Hathaway Annual Meeting Q&A