I’ve seen this written or referred to on four or five different blogs, so I’ll just credit the original writer. (Okay, also as cited by JollyBlogger.)
I am the sort of man who writes because he has made progress, and who makes progress by writing.
— Augustine, Epistle 143.2-3
I cannot say that I am any sort of man. But for me, part of progress is processing, and processing is done by writing, so it’s kinds of the same thing.