Designed for the semester or quarter course that is often called 'The Rationalists', this anthology is a slightly revised and expanded version of the relevant sections of Modern Philosophy: An Anthology of Primary Sources. It contains the complete text of Descarte's Meditations and Leibniz's Monadology and substantial selections from Spinoza's Ethics, along with other key texts of the period -- in whole or in part -- which enhance the reader's understanding of modern philosophy and its relationship to the natural science of the time.