What is a good exercise for developing my critical thinking ability?
I have four very basic suggestions that I always recommend to my students. These are not ‘tricks’ but rather, attitudes and practices that are, in my opinion, fundamental to learning how to be a better critical thinker.
That said, #2 and #3 can be considered exercises. They work best when practiced in the context of #1 and #4.
Critical thinking is about understanding, not about convincing. So keep an open mind. If you are debating a topic (like almost anything in religion, politics, or philosophy) on which reasonable people can disagree, then it is very unlikely that you are 100% right. Remember that you might have to admit you’re wrong about something. You might even eventually have to change your conclusions.
On any topic you really care about, find, read, listen to, and carefully consider well-argued positions that you disagree with. Do this as often as possible. A critical mind cannot be developed in a context of constant agreement. Only dealing with disagreement will help you develop your critical faculties. But you need to find strong arguments that will actually challenge you; not weak ones that can be quickly dismissed.
Argue against yourself! Try to find your own strong arguments in favour of positions you disagree with. Don’t create straw man arguments or red herrings: try to build arguments in favour of your opponent’s point of view, making your arguments as strong as possible.
Then, once you have found arguments in favour of positions you think are wrong, you will be able to defend your own position more adequately. If there are no strong arguments at all in favour of the other position, then try to put yourself in the other person’s shoes to figure out why they think as they do.
Or, as I said under #1, you might end up convincing yourself of the other point of view. And that’s ok!
If you’re using your critical thinking skills in the context of a debate, then regardless of your own point of view or how heinous you think are the other person’s ideas and arguments, never resort to name-calling, never try to replace real arguments with rhetorical questions, and never change the subject while pretending that you’re still on-topic.
Never use strategies like this. Such tactics only show disrespect for the person you’re addressing and make it appear (or prove) that your arguments are weak.
Critical thinking is about facing the facts and being ready to accept the strongest argument. Obviously, for that you also need to learn what makes an argument a strong one and what makes a claim reliable. But once you have started down this path you’ll find that, as with every other skill, you will get better at it with practice.