As a result of human cognition, knowledge is a very extended concept. It generally includes four levels or aspects, that is, common sense, a generalization of experience, scientific knowledge, and philosophical knowledge. The so-called common sense mainly includes aphorisms, proverbs and other commonly known knowledge It is often not an understanding of the nature of things and their laws. Scientific knowledge is a theoretical system that is logical and systematic. This sentence supports an argument, namely:. ['Scientific knowledge is absolute truth and beyond doubt.', 'Compared with scientific knowledge, common sense has a lot of scrutinies, that is, it contains many errors.', 'Common sense is not credible.', 'Scientific knowledge contains common sense.']