William James spent years documenting what he called 'the will to believe' — the way a scientist's prior conviction actively shapes what counts as sufficient evidence to them. His 1896 lecture argued that in genuinely underdetermined situations, choosing to believe something can make it true, the way believing a rope bridge will hold makes you cross it more firmly and actually survive. This sounds like a defense of wishful thinking, but James was making a subtler point: scientists who demand absolute certainty before committing to a hypothesis are also making a will-to-believe choice — the choice to let the question stay dead. What he noticed, and what experimental psychology has since confirmed through work on motivated stopping rules, is that 'I need more data' is not a neutral position. It is a wager, just an invisible one. The practical consequence for any serious scientific or intellectual project is this: periodically audit your stopping conditions. Not whether your evidence is strong enough — but who decided what 'strong enough' means, and when that decision was made.

In your current most active scientific or intellectual project, what would it take to convince you that you were wrong — and did you set that standard before or after you saw the results?

Drawing from American Pragmatism — William James (The Will to Believe, 1896)