No one has yet been found so firm of mind and purpose as resolutely to compel himself to sweep away all theories and common notions, and to apply the understanding, thus made fair and even, to a fresh examination of particulars. Thus it happens that human knowledge, as we have it, is a mere medley and ill-digested mass, made up of much credulity and much accident, and also of the childish notions which we at first imbibed.
The science [geometry] is pursued for the sake of the knowledge of what eternally exists, and not of what comes for a moment into existence, and then perishes.
There is nothing so charming as the knowledge of literature; of that branch of literature, I mean, which enables us to discover the infinity of things, the immensity of Nature, the heavens, the earth, and the seas; this is that branch which has taught us religion, moderation, magnanimity, and that has rescued the soul from obscurity; to make her see all things above and below, first and last, and between both; it is this that furnishes us wherewith to live well and happily, and guides us to pass our lives without displeasure and without offence.
Is not prayer also a study of truth,--a sally of the soul into the unfound infinite? No man ever prayed heartily, without learningsomething. But when a faithful thinker, resolute to detach every object from personal relations, and see it in the light of thought, shall, at the same time, kindle science with the fire of the holiest affections, then will God go forth anew into creation.
It is commonly observed that a sudden wealth, like a prize drawn in a lottery or a large bequest to a poor family, does not permanently enrich. They have served no apprenticeship to wealth, and with the rapid wealth come rapid claims which they do not know how to deny, and the treasure is quickly dissipated.
Wisdom without love is like having lungs but no air to breathe. Do not seek wisdom in order to acquire knowledge but in order to live and love more fully.
We assume a common sense as the necessary condition of the universal communicability of our knowledge, which is presupposed in every logic and every principle of knowledge that is not one of skepticism.
Conversation with a friend will only bear good fruit of knowledge when both think only of the matter under consideration and forget that they are friends.
Man, being the servant and interpreter of Nature, can do and understand so much and so much only as he has observed in fact or thought of the course of nature; beyond this he neither knows anything nor can do anything.