| I think evolution and economics are great subjects for the development of critical thinking because it is easy to develop a great deal from intuitive "first principles." Once you understand the basic assumptions of economics you can "prove" all of microeconomics. Similarly, once you understand evolution, which is at its heart pretty simple, you can use it to analyze any feature of biology, from plant cell structure to human culture. On the other hand, subjects like chemistry rely on a lot of facts simply handed down by authority; you won't learn how they were discovered or their basic principles until you advance far down the road (its not intuitive).
Although philosophy is in theory great for critical thinking skills, a lot of philosophers are quite bad at it, so I can only suggest logic courses in that field.
Anthropology and history are good for critical thinking because they present you with other worldviews and ways of living, giving you a broader prospective. |