Quotes about Know thyself

Cicero famously said, you have no choice between having a philosophy and not having one, only between having a good one and having a bad one. And not to admit that you have a philosophy at all is to have a bad one. For it is one that does not know itself. So how could it know anything else, especially us?

Of all the beautiful truths pertaining to the soul None is more gladdening or fruitful than to know You can regenerate and make yourself what you will.