Asked in Critical Thinking
What is the difference between common sense and critical thinking?
It's not like instinct, and can be highly prejudiced.
Say it's local optimization, and different even within a culture.
Critical Thinking is 'rational optimization' of 'rational' aspects. It provides a 'rational' optimum, for instance not considering most emotional aspects. And often ignoring most cultural differences.
The purpose of Common Sense is to enable one to function "well" inside the society - that is, its purpose is to provide a framework for making the "proper" decision when faced with a commonly-occurring problem or issue. As pointed out above, Common Sense is thus highly cultural and locale-specific, as the entire purpose of it is to make your immediate life easier inside your community. Thus, it tends to be a collection of "works best" approximations, rather than some logical framework for deduction of truth.
Critical Thinking (or better: Critical Analysis) is a discipline of Logic, wherein a framework of principles has been created to discover the cause, impetus, and possible outcome(s) of a situation. This framework focuses on factual events and uses the theories of logical analysis and deduction to postulate WHY something happened, and WHAT the possible impacts are of different responses to the problem/issue.
Critical Thinking can (and should) consider the emotional and cultural impact of an outcome, but is NOT driven by those considerations, unlike Common Sense, in which those two factors are primary. Additionally, Common Sense generally supports the theory that for every problem, there is a single correct solution. Critical Thinking is not about finding the correct solution, as "correct" is impossible to define logically (in this area). Instead, Critical Thinking is about discovering the actual costs and benefits of various solutions. Critical Thinking does not dictate a choice of solution, but rather is intended to inform choice in as rational manner as possible.
In the end, Common Sense is a "dictator" of action, while Critical Thinking is an "adviser" of action: Common Sense tells you what to do in a situation, while Critical Thinking informs you of the consequences of a range of actions.