DESCARTES AND LOCKE (Knowledge) One of the most important branches in philosophy, is Epistemology, which means, theory of knowledge. So far, philosophers have made many attempts to discover the source of knowledge, the standards or criteria by which we can judge the reliability of knowledge. We tend to be satisfied with think what we know about almost everything, even though sometimes we are shocked to discover that something that we thought it was sure and certain, is instead proved dubious and not sure. For example, suppose that one person that you know and trust tells you th