Immanuel Kant (1724-1804) was one of the world's most unique philosophers. He wrote such works as his "Copernican Revolution" and "The Critique of Pure Reason". Although many philosophers believe that time is all around us and we are merely trapped inside of time, Kant described time as "the form of inner sense". Kant states that time and all things related are a priori (instinctive) perceptual features of man's nature.
Time is a mental construct, a priori to culture conditioning. It is inside the head, not outside of it. Time does not exist in the physical world because it has no physical attributes. Kant says that "the mind will trick itself into thinking that objects around it are "in" time" (Time and Space). We think that because we have a word for time, that it exists around us. Time does not exist around us, we merely see things around us in the form of time. Time is a thought - a way of thinking. Time is not tangible. It has no existence in the physical world, only in the mental world. Time is a mental construct that only exists in the mind.
Time is a mode of perception. A "mode" refers to the way something is done. "Kant's idea was that time and space belong to the human condition. "Time and space are the first and foremost modes of perception and not attributes of the physical world" (Gaarder, 1996). The mind sees things in relation to time. Time cannot exist on its own because it is conceived in the mind, it is a priori. Time is a mode of perception we use to see and understand things in the physical world.
Time is an a priori feature of the mind. It keeps things in order. The world we experience is full of disordered and chaotic sensations that the mind tries to organize. The basic system of order that the mind uses is what we call time. "Time is a necessary representation, lying at the foundation of all our perceptions." (Velasquez, 2002). A priori spatial considerations organize sensations into objects and tries to relate these objects to one another in the world of space.