The Alphabet of Thinking

Explain how a system based on 'belief' without evidence can possibly be called a system of thought.

I was asked this question when dialoguing with an atheist. This misunderstanding is common; that the Catholic faith is based on ‘belief’ and that their position (i.e. science) does not require a leap of faith. There is evidence for the Catholic faith, although the faith is not provable. Science is the same in this regard. Science, and all systems of thought, rests on premises that cannot be proven. Science itself does not pass by the standard of provability by which they reject the Catholic faith and we need to make this known. The following is a quote, from G.K. Chesterton, that explains the situation very well.

What modern people want to be made to understand is simply that all argument begins with an assumption; that is, with something that you do not doubt. You can, of course, if you like, doubt the assumption at the beginning of your argument, but in that case you are beginning a different argument with another assumption at the beginning of it. Every argument begins with an infallible dogma, and that infallible dogma can only be disputed by falling back on some other infallible dogma; you can never prove your first statement or it would not be your first. All this is the alphabet of thinking…Much of our chaos about religion and doubt arises from this--that our modern sceptics always begin by telling us what they do not believe. But even in a sceptic we want to know first what he does believe. Before arguing, we want to know what we need not argue about. And this confusion is infinitely increased by the fact that all the sceptics of our time are sceptics at different degrees of the dissolution of scepticism. Philosophy for the Schoolroom