Jean-Jacques Rousseau said this quote
“ Are your principles not engraved in all hearts, and in order to learn your laws is it not enough to go back into oneself and listen to the voice of one's conscience in the silence of the passions? There you have true philosophy. Let us learn to be satisfied with that, and without envying the glory of those famous men who are immortalized in the republic of letters, let us try to set between them and us that glorious distinction which people made long ago between two great peoples: one knew how to speak well; the other how to act well. ”