It seems certain, that though a man, in a flush of humour, after intense reflection on the many contradictions and imperfections of human reason, may entirely renounce all belief and opinion, it is impossible for him to persevere in this total scepticism, or make it appear in his conduct for a few hours.
David HumeWhere ambition can cover its enterprises, even to the person himself, under the appearance of principle, it is the most incurable and inflexible of passions
David HumeIt seems to me, that the only Objects of the abstract Sciences or of Demonstration is Quantity and Number, and that all Attempts to extend this more perfect Species of Knowledge beyond these Bounds are mere Sophistry and Illusion.
David Hume