Substance is• Conceived only through itself and exists in itself. We need no other concept to conceive it or explain its cause• Infinite. Substance has infinite attributes, each of which expresses infinite essence.• Unitary• Immanent• Most perfect and powerful. • God

Composition of Extensive BodiesSimplest Bodies

•Are neither atoms nor made of any smaller components

•Are only distinguishable in terms of their motion and rest, speed and slowness, and not in terms of their make-up

•Affect each other’s motion by means of their physical impacts

•Combine to form larger bodies when they communicate their motions in some fixed ratio

Composition of Extensive BodiesComposite Bodies: higher and higher scales of composition

Euclid, Elements, Book III, Prop 35:If in a circle two straight lines cut one another, then the rectangle contained by the segments of the one equals the rectangle contained by the segments of the other.

Objective and Formal Reality

“the idea is objectively in the same way as its object is really.” [41]