If you can't trust a teacher or a textbook, then you are in big trouble. Especially if it is a brand new subject to yourself where you don't have an intuition about what is correct/incorrect. Part of a teacher/student relationship is obviously trust.
No, you aren't. You can listen to ideas and think about them and attribute them to the sources and come to (or not) your own conclusions.
The reason it's such a bad idea to "trust" the way you are suggesting is that many fields are quackery. Do you trust that fancy textbook and sophisticated sounding professor from first year macroeconomics?
