If you're building a Critical Thinker, à la Dr Frankenstein, here are the abilities and attributes you need:
Tolerance: Critical Thinkers delight in hearing divergent views, and enjoy a real debate.
Analytical skills: Critical Thinkers don't accept just any kind of talking. They want properly constructed arguments that present reasons and draw sound conclusions.
Confidence: Critical Thinkers have to be a little bit confident to be able to examine views that others present — often people in authority.
Curiosity: Critical Thinkers need curiosity. It may have killed the cat, but curiosity is the essential ingredient for ideas and insights.
Truth-seeking: Critical Thinkers are on mission ‘objective truth’ — even if it turns out to undermine their own previously held convictions and long-cherished beliefs and is flat against their self-interest.