Every single thing he did was a result of conscious decisions. Yes he did know exactly what he was doing. Many years ago I studied the history of art at university and we all went off to Paris for the galleries. When I saw his Sunflowers in the flesh I was blown away. The 3D texture of his paintings is lost on a flat page in a book. I just wanted to reach out and run my fingers over the surface, not allowed, of course.But make the effort to go and see his art. You will never forget it.