Meditations on First Philosophy

Essence is the most fundamental nature of a substance and is what constitutes its definition. For the human subject, it is thinking. For God, it is existence itself.

How something comes into the world as a knowable entity. The existence of himself and God are Descartes’s primary interests.

God, for Descartes, is infinite and the most clear and distinct thing a subject can know. God is the most perfect truth because He retains His objectivity. In knowing God more completely, one comes to know more distinctly the objectivity attributed to things by Him.

Descartes equates knowledge of pure mathematics to knowledge of God. Pure mathematics concern the modes of substance such as breadth, motion, and extension. As such, pure mathematics are how the soul comes to know the substance clearly and distinctly.

Descartes states early on that the mind and soul are indistinguishable. The mind/soul is indivisible and immortal. It grasps the modes of the substance, such as extension, breadth, and width, otherwise known as pure mathematics.

Particulars are considered finite insofar as they pertain to an entity and are susceptible to change or alteration. They are perceivable by the subject and pertain to how the object presents itself to the observer.

The senses are a source of adventitious truths for Descartes but an unreliable source. They provide useful knowledge concerning their bodies and external objects that aid survival. Yet, the senses deceive insofar as, for example, we may perceive something far away as small when it is large.

A substance is a composite of matter and form. It possesses both particulars, or finite determinates, and universals, or objective truths.

Descartes’s philosophy is subject-oriented insofar as external objects are filtered through the thinking subject. Thinking is the essence of the human subject. Furthermore, each time this statement is affirmed, it provides a subsequent confirmation of being.