[jtsuken]

> Probability has been understood at a quantitative level since Laplace [...] and Kolmogorov.

Which indicates it is roughly as hard as partial differential equations, the theory of relativity and just a tiny bit easier than some of the quantum mechanics.

This is pretty unintuitive for a subject, which mostly relies on multiplication and addition.

The dozen or so posts discussing the intuition of the Monty Hall Problem are a case in point.

> They are an appetizer, not the main dish.

This is certainly true.