The reluctance to admit that it is permissible to believe without evidence even in a truth so undisputed as the Uniformity of Nature, is also in part due to yet another cause. It is felt that to admit belief without regard to evidence is to invite intellectual anarchy, and to leave mankind the helpless prey of ignorance, error, and superstition. Hence, in many candid souls, a lamentable feeling of distraction and hopelessness: to abandon their old faith, even if it has no evidence, is almost more than they can bear; to retain it, knowing that it has no evidence, is to open the floodgates of a saturnalia of unreason by which the foundations of civilisation would be swept away. Hence, too, the zeal with which other minds call for the destruction of every belief, but especially religious belief, not based on evidence, and with which they denounce faith as the one unpardonable sin. But the error into which both classes of mind fall is a simple one. It consists in imagining that if we take one thing on faith, because there is no evidence, therefore we may believe anything, even if the evidence is conclusive against it--that if we once accept faith, we must for ever abjure reason. The error has been clearly exposed by Professor Huxley, who, after pointing out that reason--ratiocination--is based on faith, says, "But it is surely plain that faith is not necessarily entitled to dispense with ratiocination because ratiocination cannot dispense with faith as a starting-point; and that because we are often obliged, by the pressure of events, to act on very bad evidence, it does not follow that it is proper to act on such evidence when the pressure is absent."[35] It seems, then, a piece of alarmist exaggeration to say that if we admit one thing, _e.g._ the Uniformity of Nature, without evidence, we forfeit the right ever again to ask for evidence for any other statement: on the contrary, whenever evidence can be got, we must get it and abide by it. But this only shows that no disastrous consequences will necessarily ensue, if we frankly admit what in any case is the fact, viz. that there is no evidence for the postulate on which all science is built. You will not have committed high treason against the best interests of mankind by acting, in this case, on the principle that a man may sometimes believe a thing on evidence which, he is well aware, is insufficient, or on no evidence at all. On the other hand, in another case, to act on the principle might be, if not high treason, at least mischievous.