The church was very tough on early scientists. It was not only unprofitable but often deadly to suggest reasons for anything other than the will of God. Descartes stepped forward and addressed a great many of the church's fears. None the less, he was very unpopular in his time and his works were banned by the Pope.

Take a look at the fools today who are still unconvinced by the scientific method. Now expand that back in time a half-millenia and you have something of an idea as to how the literate Western world responded to his assertions.

Without René Descartes there would probably not be any modern sciences including advances in math, technology, and medicine.