Rationalism holds that knowledge is attained by ignoring reality while relying on deduction from arbitrarily formed concepts. This method dominates contemporary philosophy. To understand rationalism's ascendancy, this course will trace its 19th and 20th century philosophical progression. We will study how rationalism advanced through Hegel and Russell, and the figures responsible for its invasion of American philosophy (e.g. Royce, Bradley, Whitehead), culminating with Quine, symbolic logic, "possible worlds," and "brains in a vat."