A man was meant to be doubtful about himself, but undoubting about the truth; this has been reversed. Nowadays the part of a man that a man does assert is exactly the part he ought not to assert - himself. The part he doubts is exactly the part he ought not to doubt - the Divine Reason.
If a person offends you, and you are in doubt as to whether it was intentional or not, do not resort to extreme measures; simply watch your chance, and hit him with a brick.
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.
Reagan did not suffer from the dismal plague of doubts which has assailed so many politicians in our times and which has rendered them incapable of clear decisions.
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.