A colorblind painter looks at his painting and out at his world with his colorblind eyes and asks “If there were a problem with my vision, wouldn’t that be apparent in my painting?”

With whatever capacities we have for conceiving truth, we recognize truths in our experience. With whatever capacities we have for conceiving truth, we have a sense of how everything hangs together. With whatever capacities we have for conceiving truth, we compare the truth of our experience with what we know to be true and find that they match. “If there were a problem with how I think thinking, wouldn’t my errors be apparent in my thoughts?”