And as this is the obvious appearance of things, it must be admitted, till some hypothesis be discovered, which by penetrating deeper into human nature, may prove the former affections to be nothing but modifications of the latter. All attempts of this kind have hitherto proved fruitless, and seem to have proceeded entirely from that love of simplicity which has been the source of much false reasoning in philosophy.
David HumeLet us become thoroughly sensible of the weakness, blindness, and narrow limits of human reason: Let us duly consider its uncertainty and endless contrarieties, even in subjects of common life and practice.... When these topics are displayed in their full light, as they are by some philosophers and almost all divines; who can retain such confidence in this frail faculty of reason as to pay any regard to its determinations in points so sublime, so abstruse, so remote from common life and experience?
David HumeFor my part, when I enter most intimately into what I call myself, I always stumble on some particular perception or other, of heat or cold, light or shade, love or hatred, pain or pleasure. I never can catch myself at any time without a perception, and never can observe anything but the perception.
David Hume..all arguments concerning existence are founded on the relation of cause and effect; that our knowledge of that relation is derived entirely from experience; and all our experimental conclusions proceed upon the supposition that the future will be conformable to the past. .... Without the influence of custom, we should be entirely ignorant of every matter of fact beyond what is immediately present to the memory and senses.
David Hume