Priori knowledge refers to knowledge that is independent of experience. It is often associated with concepts that can be understood through reasoning and logic alone, such as mathematical truths or definitions. For example, knowing that 2 + 2 = 4 does not require empirical evidence; it is derived from the understanding of numbers and addition. In philosophy, Immanuel Kant distinguished between a priori and a posteriori knowledge, the latter being knowledge gained through experience. A priori knowledge is considered universal and necessary, meaning it holds true regardless of individual experiences or observations. This type of knowledge plays a crucial role in fields like mathematics and logic.