An intellectual is going to have doubts, for example, about a fundamentalist religious doctrine that admits no doubt, about an imposed political system that allows no doubt, about a perfect aesthetic that has no room for doubt. ↗
Fear is not in the habit of speaking truth; when perfect sincerity is expected, perfect freedom must be allowed; nor has anyone who is apt to be angry when he hears the truth any cause to wonder that he does not hear it. ↗
A good businessman never makes a contract unless he's sure he can carry it through, yet every fool on earth is perfectly willing to sign a marriage contract without considering whether he can live up to it or not. ↗