" In addition to such public chastisement Spinoza received a number of letters intended to reform him; that of a former pupil, Albert Burgh, who had been converted to Catholicism, may be taken as a sample:

You assume that you have at last found the true philosophy. How do you know that your philosophy is the best of all those which have ever been taught in the world, are now taught, or shall be taught hereafter? To say nothing of what may be devised in the future, have you examined all those philosophies, both ancient and modern, which are taught here, in India, and all the world over? And even supposing that you have duly examined them, how do you know that you have chosen the best? How dare you set yourself up above all the patriarchs, prophets, apostles, martyrs, doctors, and confessors of the Church? Miserable man and worm upon the earth that you are, yea, ashes and food for worms, how can you confront the eternal wisdom with your unspeakable blasphemy? What foundation have you for this rash, insane, deplorable, accursed doctrine? What devilish pride puffs you up to pass judgment on mysteries which Catholics themselves declare to be incomprehensible? Etc., etc.

To which Spinoza replied:

You who assume that you have at last found the best religion, or rather the best teachers, and fixed your credulity upon them, how do you know that they are the best among those who have taught religions, or now teach, or shall hereafter teach them? Have you examined all those religions, ancient and modern, which are taught here, and in India, and all the world over? And even supposing that you have duly examined them, how do you know that you have chosen the best? "

― Will Durant , The Story of Philosophy: The Lives and Opinions of the World's Greatest Philosophers