>>11476772He wrote Le discours de la Méthode which is a the first real book about rationalism even though it's proto-rationalism.
Before him all topics were pretty much discussed based on God and the bible or some ancient author instead of deduction and logic.
If you read it you will probably realize it's a bit messy but back in his days his "method" was revolutionary stuff because it didn't rely on an appeal to authority but basic principles of logic.
Basically it advocates starting with the most basic principles of logic/reason and then using them to answer questions.
Empiricism and rationalism coupled together are pretty much the origins of the modern scientific method, arguably mathematicians are more rationalists while physicists would be empiricists.
