Aristotle believed people would engage in philosophical investigations because they were curious. The world was filled with puzzling things. People wondered about them.

He believed that a beginner should first attend to the appearance of things and then consider opinions people offer about the nature of those things. This way, the beginner could build upon what earlier generations had learned about those same things. Following careful consideration, if the opinions seem solid, this was proof enough of their validity.

But if the opinions contradicted one another or seemed to be mistaken after due study, this was the time to engage in more observation and theorizing.