The system of Descartes... seemed to give a plausible reason for all those phenomena; and this reason seemed more just, as it is simple and intelligible to all capacities. But in philosophy, a student ought to doubt of the things he fancies he understands too easily, as much as of those he does not understand.
This self-love is the instrument of our preservation; it resembles the provision for the perpetuity of mankind: it is necessary, it is dear to us, it gives us pleasure, and we must conceal it.
Every man can educate himself. It's shameful to put one's mind into the hands of those whom you wouldn't entrust with your money. Dare to think for yourself.