# Lesson 3 – Classical Principal

In this lesson, part of “The Art of Thinking” series, we explore the classical principles of thought, which are considered guides of reason. The first principle is the principle of identity, which asserts that everything is something in particular. This principle is crucial to thinking and conversation, as it enables us to understand things as they are and communicate accurately with one another. The second principle is the principle of excluded middle, which states that for any claim, either it’s true or its contrary is true. The third principle is the principle of non-contradiction, which guides our thinking by asserting that two halves of a contradiction cannot both be true at the same time. By understanding and applying these classical principles of thought, we can sharpen our reasoning skills and come closer to understanding what is true.