Frank Knight’s spin on Hume’s induction paradox.

Brilliant observation from Knight’s Risk Uncertainty and Profit: “We live in a world full of contradiction and paradox, a fact of which perhaps the most fundamental illustration is this: that the existence of a problem of knowledge depends on the future being different from the past, while the possibility of the solution of the problem depends on the future being like the past.”

I see this as an extension of Hume’s more famous induction paradox: “Why should we believe that the sun will rise again in the East tomorrow?” To say that because “its always risen in the East before” is not a reason — its simply a restatement of the belief. Hume’s answer is that there can in fact be no “reason” — its a matter of animal instinct.

This kind of animal instinct makes many kinds of “routine” knowledge problems trivial. The interesting ones become “when or how might the future be different from the past (or how could we make it different)”? And whatever mental process we use (eg the application of science) relies on some ‘likeness’ with past situations. Note “likeness” is crucial. If “identical” we could fall back on the simple animal instinct of extrapolation.