Ordinary definitions of critical thinking usually describe it as a combination of abilities: understand information, synthesize it, and use discipline-based skills like reading, writing, and math to make sense of it. While it is true that critical thinking cannot proceed without these skills—the skills we call intellectual competence—critical thinking goes one step beyond intellectual competence. The one step beyond critical thinking is crucial: meta-cognition. Without meta-cognition, we may believe that we understand what we analyze, or that we have synthesized what we know into a basic understanding of a social problem, but if we fail to step back from our reasoning and subject it to skeptical scrutiny, we may never realize that we are trapped in a solipsistic bubble of social injustice. Meta-cognition is the practice of analyzing how we think after the fact by way of reflection and, when necessary, self-correction. In this chapter, we focus on defining the kind of critical thinking demanded by the social sciences, the humanities, and beyond.