What is the "simple definition" of critical thinking that wraps up the topic?

"Critical thinking is the careful analysis of beliefs, arguments, and positions in order to reach correct conclusions."

After all the machinery — virtues, standards, fallacies, biases — it boils down to one sentence: critical thinking is the careful analysis of beliefs, arguments, and positions, aimed at reaching correct conclusions. Two halves matter equally:

• Careful analysis — the method: examining beliefs and arguments deliberately rather than accepting them.
• To reach correct conclusions — the goal: it's truth-directed, not analysis for its own sake or for winning.

This pairs with a short list of the attitudes a critical thinker brings: openness to the possibility of being wrong; willingness to hear out others' arguments; the ability to take criticism without reacting emotionally; willingness to question one's own convictions; a commitment to genuinely understand others' views before rejecting them; a commitment to avoid unclear language and bad arguments; and willingness to respect well-grounded opposing views.

Tip: The definition is method + goal: careful analysis (how) aimed at correct conclusions (why). Strip either half and it stops being critical thinking — analysis with no truth-goal is just nitpicking.