For, dear me, why abandon a belief, Merely because it ceases to be true, Cling to it long enough, and not a doubt, It will turn true again, for so it goes.
you must be careful never to allow doubt to paralyze you. always take the decisions you need to take, even if you're not sure you're doing the right thing. You'll never go wrong if, when you make a decision, you keep in mind an old German proverb: 'The devil is in the detail.' Remember that proverb and you'll always be able to turn a wrong decision into a right one.
It would be too ridiculous to go about seriously to prove that wealth does not consist in money, or in gold and silver; but in what money purchases, and is valuable only for purchasing. Money no doubt, makes always a part of the national capital; but it has already been shown that it generally makes but a small part, and always the most unprofitable part of it.
Everyone who observes himself doubting observes a truth, and about that which he observes he is certain; therefore he is certain about a truth. Everyone therefore who doubts whether truth exists has in himself a truth on which not to doubt.... Hence one who can doubt at all ought not to doubt the existence of truth.