I have resolved to demonstrate by a certain and undoubted course of argument, or to deduce from the very condition of human nature, not what is new and unheard of, but only such things as agree best with practice.
Baruch SpinozaIf we love something similar to ourselves, we endeavor, as far as we can, to bring it about that it should love us in return.
Baruch SpinozaThe terms good and bad indicate no positive quality in things regarded in themselves, but are merely modes of thinking or notions, which we form from the comparison of things one with another. Thus one and the same thing can be at the same time good, bad, and indifferent. For instance, music is good for him that is melancholy, bad for him that mourns; for him that is deaf; it is neither good nor bad.
Baruch Spinoza