It's like this, I think: the excellence of a good body doesn't make the soul good, but the other way around: the excellence of a good soul makes the body as good as it can be.
PlatoIn the world of knowledge, the essential Form of Good is the limit of our inquiries, and can barely be perceived; but, when perceived, we cannot help concluding that it is in every case the source of all that is bright and beautiful -in the visible world giving birth to light and its master, and in the intellectual world dispensing, immediately and with full authority, truth and reason -and that whosoever would act wisely, either in private or in public, must set this Form of Good before his eyes.
Plato