You can overpay for anything if someone dumber is lined up behind you

An asset can be a rational buy even at an absurd price, so long as you expect to resell it to a 'greater fool' before the music stops. The theory explains why people keep buying into obvious bubbles — not because they are naive, but because they're betting on everyone else's naivety rather than the asset's actual worth. It only breaks down when every buyer is simultaneously trying to be the one who sells first.

— Burton G. Malkiel, A Random Walk Down Wall Street — Chapter 2, 'The Madness of Crowds' (1973)
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