Though it’s probably crazy to do this if we’re discussing the history of philosophy, for the purposes of keeping within boundaries of this presentation we’re going to skip over Socrates, who is an eminent figure in the history of philosophy, notwithstanding. We are going to go directly to two thinkers that understood what the Pre-Socratics were trying to do. These two philosophers took it up a notch: Plato, student of Socrates, and then Aristotle who was a student of Plato.
Plato. According to Plato, the underlying unity that is necessary to make sense of things is not found in the world, i.e. in the world of sensory experience, what we can feel, eye, touch, taste, and hear. Senses can deceive us. In effect Plato split reality into two worlds; the world of the “forms” and the world of sense experience. The forms are perfect and without flaw; immaterial, you can’t touch, smell, hear, or taste them. They can only be grasped by the mind. They are changeless, stable so therefore all can be understood by reference to them. They act as the eternal, unchanging blueprints or receipt for all thing in the material, whether physical (like trees or dogs), or abstract qualities (like goodness, justice, redness, etc.). When things are similar, it is because they derive from the same form. The perceptual world consists of imperfect copies of the forms. Imperfect, so that they are not exactly the same as one another, but the similarity is based on the form that they are defective copies of.
Here’s a quick example: According to Plato’s doctrine of the the “forms” there exists in the eternal world a form of “treeness.” This form possesses all the necessary qualities that make a tree a tree. Every single tree down here in the physical world is patterned after this form of treeness. Down here, all tree are but imperfect copies of the form, and that’s why no two trees are exactly alike here in our world. Things in the perceptual world are perishable, because of their imperfection and changeability.
Aristotle. Aristotle does away with the platonic idea of the Forms. They are way too
other worldly for him. Forms, for Aristotle, are not found in a separate world, it is rather an element of a thing in the world. The form is not “out there” but instead, the form is found “in the thing” itself. Now he sees things in the world, through the category of substance. A substance is an individual thing, a person, chair, etc. These things, these substances, are a combination of form and matter. Form is what a thing is, the whatness of a thing. Matter, is what it is made of, the thisness, that which makes it this particular thing. Brad Pitt and I share the same form, the form of man. Matter is what makes him that particular man (a much better looking man).
According to Aristotle, only the unmoved mover (Aristotle’s deistic god) is pure form without matter. It is the one exception to his rule. The unmoved mover is not influenced by anything in the world, yet it is what causes all motion, all change. The unmoved mover is the final answer to that ever so popular question, with not only kids but also with adults, “what caused this to happen?” A is explained by B, B by C, you eventually get to the unmoved mover and nothing caused it to happen. Unmoved mover is an abstract entity not a person; it does not have personality characteristics.