[Editor's Note: We do not know the name of Clarke's correspondent. Clarke's letter dealt extensively with the issue of divine immensity and its compatibility with the fact that God is an immaterial thinking substance. It should be read in conjunction with supplementary text 1. The text is from Wii, 751–4]

Sir,

You will give me leave, without any preface or apology, to propose directly the best answer I can to the objections you have offered.

There are but two ways by which the being and all or any of the attributes of God can possibly be proved. The one, a priori; the other, a posteriori.

The proof a posteriori is level to all men's capacities because there is an endless gradation of wise and useful phenomena of nature, from the most obvious to the most abstruse, which afford at least a moral and reasonable proof of the being of God to the several capacities of all unprejudiced men who have any probity of mind. And this is what, I suppose, God expects, as a moral governor, that moral agents should be determined by.