On his blog a few years ago, Terence Tao wrote about what he observed as the three distinct stages of mathematics education. He called them “pre-rigorous”, “rigorous”, and “post-rigorous” respectively. As I reflect on how the way I think skeptically has change over the years, I find that it’s similar to how Terence Tao described about math. I’ll roughly divide it into the following stages.

1. The “pre-skeptic” stage, where skeptic thinking is only used selectively (and relatively rarely). There is a sense of naive optimism, where people, writings, and thoughts are mostly trusted at first encounter, on their good will. Ideas flourish almost uncontested, and the good and bad are separated by trying them out.
2. The “total-skeptic” stage, where every conscious effort of thinking is dominated by skepticism. This is where every thought, from others or self alike, are always met first with serious doubt. New ideas are always contested in the mind, where most of the good and bad separation happens. Ideas are almost always rejected, because rarely can they stand up to the process of skeptic questioning. There is usually an accompanying sense of pride when rejecting ideas via some sophisticated rationalist argument.
3. The “post-total-skeptic” stage, where skepticism still occupies a major part of thinking, but with a re-connection to the optimism of the “pre-skeptic” stage. Ideas are still evaluated with a critical, skeptic lens, but are not outright rejected if the mental tests are not passed. Most ideas are still totally rejected, but some are allowed to flourish even when the skeptical analysis deems them bad.

The first and second stage has quite a chasm between them, because I think their underlying world view is different. In the “pre-skeptic” stage, people are seen, by default, as good (as in good willed) and capable, while in the “total-skeptic” stage, people are seen as malicious (“you are lying to me”) or incompetent (“you are wrong but do not realize it”) or both. The transition typically happens when one has been burned by enough bad experiences (“seen enough shit to know better”). A total skeptic is very jaded, and can appear cold, mean, apathetic, and risk-averse.

Skepticism can turn on itself, described in Pascal’s Wager as “it is not certain that everything is uncertain”. This is often the trigger for the transition between the second and third stage, at least in my own experience. A post-total-skeptic still thinks skeptically, but that skepticism is nested in a more positive, optimistic foundation, similar to the one in the “pre-skeptic” stage. The difference though, is that this optimism is not naive, but stems from a humble realization of the limits of one’s own ability and rationality.