I think (it's not my post) that it's supposed to be evidence that numbers are real because the set of all possible minds is vast. Because there are so many possible minds, it's unlikely that a mind chosen randomly from that set would have similar intuitions about numbers to mine. It's even more unlikely that a third mind would also have those intuitions. Yet, for some reason, this vastly unlikely thing happens anyway. This implies that there is some reason which is responsible for all the minds feeling the same way. One such reason would be "the intuition is correct, and the minds have correctly figured it out".

(Other possible reasons could be "all the minds are biased in the same way" or some other reason unrelated to truth of the idea, but nobody's saying it's proof, it's just evidence.)

Here's my solution. A statement is a grouping of symbols(which is what words are) and can, itself, be treated as a symbol. Symbols are used to refer to something other than themselves, but when you have the statement refer to itself, you get a paradox. When it refers to itself it becomes infinitely interpretable causing "This statement is false." to cycle between True and False for as long as you try to interpret it.

I do not like "steep learning curve" the way people use it. It raises my probability estimate that person using it has done no study of learning. This reduces my probability estimate that they have sound insight about learning.

Sometimes I work with learning curves for machine learning or human learning. These curves are plots of a measure of learning (say, correct score, or number of mistakes) versus time or number of trials or number of training examples or number of iterations. When topic is hard, curve is shallow! It takes more learning to improve score or reduce mistakes. Steep learning curve means topic is easy. Mastery comes with very few repeats or little time or little data.

Does anyone know why so many use it wrong, to mean topic is hard and progress is slow? I believe Wikipedia article is right and "learning curves" must come from scientific study. How did meaning get reversed? Wikipedia article says "Arguably, the common English use is due to metaphorical interpretation of the curve as a hill to climb." but has no citation.