Rationalism reflects a reliance on reason—the philosophical idea that the fundamental starting point for all knowledge is not found in the senses or in experience, but instead can be traced back to some innate knowledge that we’re born with.

"Rationality is the art of thinking in ways that result in accurate beliefs and good decisions."

Articles

Introduction to Rationalism (DecisionLab)

Basics of Rationalist Discourse

Goddamn basics of rationalist discourse

Elements of rationalist discourse

Websites

Rationality at Less Wrong

Effective Altruism