The Complete Poetical Works of Percy Bysshe Shelley — Complete

by Percy Bysshe Shelley

The senses are the sources of all knowledge to the mind; consequently their evidence claims the strongest assent.

The decision of the mind, founded upon our own experience, derived from these sources, claims the next degree.

The experience of others, which addresses itself to the former one, occupies the lowest degree.

(A graduated scale, on which should be marked the capabilities of propositions to approach to the test of the senses, would be a just barometer of the belief which ought to be attached to them.)

Consequently no testimony can be admitted which is contrary to reason; reason is founded on the evidence of our senses.

Every proof may be referred to one of these three divisions: it is to be considered what arguments we receive from each of them, which should convince us of the existence of a Deity.

1st, The evidence of the senses. If the Deity should appear to us, if He should convince our senses of His existence, this revelation would necessarily command belief. Those to whom the Deity has thus appeared have the strongest possible conviction of His existence. But the God of Theologians is incapable of local visibility.

2d, Reason. It is urged that man knows that whatever is must either have had a beginning, or have existed from all eternity: he also knows that whatever is not eternal must have had a cause. When this reasoning is applied to the universe, it is necessary to prove that it was created: until that is clearly demonstrated we may reasonably suppose that it has endured from all eternity. We must prove design before we can infer a designer. The only idea which we can form of causation is derivable from the constant conjunction of objects, and the consequent inference of one from the other. In a case where two propositions are diametrically opposite, the mind believes that which is least incomprehensible;—it is easier to suppose that the universe has existed from all eternity than to conceive a being beyond its limits capable of creating it: if the mind sinks beneath the weight of one, is it an alleviation to increase the intolerability of the burthen?

The other argument, which is founded on a man’s knowledge of his own existence, stands thus. A man knows not only that he now is, but that once he was not; consequently there must have been a cause. But our idea of causation is alone derivable from the constant conjunction of objects and the consequent inference of one from the other; and, reasoning experimentally, we can only infer from effects causes exactly adequate to those effects. But there certainly is a generative power which is effected by certain instruments: we cannot prove that it is inherent in these instruments; nor is the contrary hypothesis capable of demonstration: we admit that the generative power is incomprehensible; but to suppose that the same effect is produced by an eternal, omniscient, omnipotent being leaves the cause in the same obscurity, but renders it more incomprehensible.

3d, Testimony. It is required that testimony should not be contrary to reason. The testimony that the Deity convinces the senses of men of His existence can only be admitted by us if our mind considers it less probable that these men should have been deceived than that the Deity should have appeared to them. Our reason can never admit the testimony of men, who not only declare that they were eye-witnesses of miracles, but that the Deity was irrational; for He commanded that He should be believed, He proposed the highest rewards for faith, eternal punishments for disbelief. We can only command voluntary actions; belief is not an act of volition; the mind is even passive, or involuntarily active; from this it is evident that we have no sufficient testimony, or rather that testimony is insufficient to prove the being of a God. It has been before shown that it cannot be deduced from reason. They alone, then, who have been convinced by the evidence of the senses can believe it.