Describe the metaphysical views of Descartes, Spinoza, and Leibniz. Focus especially on the nature and quantity of substance and the issue of how substances interact. What common threads do you find in their perspectives?   How do they disagree with one another? Which viewpoint seems strongest to you, and why?

Substance Interaction

The notion in philosophy that distinct substances (such as mind and body) have causal relations or can affect each other.

Descartes

A French philosopher, mathematician, and scientist, often referred to as the father of modern philosophy, known for his statement, "I think, therefore I am."

Spinoza

A 17th-century Dutch philosopher known for his works on ethics, politics, and religion, emphasizing the importance of rationalism and monism.