Critical thinking
Having the skills to think critically about new information is a vital skill in the modern era. Without it, people are subject to grift, pseudoscience, conspiracy, and misinformation.
Critical thinking and skepticism are often confused with being contrarian. These are not the same thing. A contrarian may offer some valid criticisms of an out-group, but will not concede any valid points they make.
The meaning of critical thinking and skepticism has been muddied in recent years by conspiracy theorists, racists and misogynists, and other misinformation peddlers who employ the language of critical thinking to what is actually institutional contrarianism.
True critical thinking is open to the evaluation of new evidence and willing to change positions if that evidence warrants it, regardless of in-group affiliation.
See Critical Thinking, Skepticism, and Reason on Wikipedia.
Also related are Science and Logic.
Ways Critical Thinking Goes Wrong
Cognitive Bias refers to the ways that we prefer interpretations of facts that conform to various prejudices. In-group affinity bias and out-group implicit bias are some of the most important ones, which is why they are referenced so often in this wiki. Fundamental attribution is another common one, where we assume people's actions are reflections of their free will, instead of situational ethics, incentives, and power dynamics.
The producers of this content are biased against embedding videos so you'll have to click the links to watch.
Logical Fallacies happen when faulty reasoning is made in the construction of an argument. Understanding and avoiding them is necessary for effective persuasion, and for truth in general. Some of the most common are the straw man, bandwagoning, false equivalence, and ad hominem, though you should take the time to familiarize yourself with all of them. Once you do you will start seeing examples of them everywhere you look, especially if you follow politics.
Is Rationality Inevitable?
Communicative Rationality is the theory that rationality is the inevitable outcome of successful communication, and that rationality is a built-in property of language. Yuval Noah Harari's book Nexus suggests otherwise, pointing to many cases throughout history where technologies that improve our ability to communicate have led to the spread of misinformation and authoritarian abuses of power. One could argue that these simply represent unsuccessful attempts at communication. In any case, regardless of whether progress trends toward reason because it is inevitable, or because we choose reason over misinformation, or because we inevitably choose reason due to determinism, we should still make that choice.
Rationality Resources
Thinking is Power has great free courses that teach critical thinking skills.
Hidden Brain - How to Open Your Mind
Hidden Brain - Revealing Your Unconscious Part 1 and Part 2