David Hume wrote:[205]
In short, I repeat the question: Is the world, considered in general, and as it appears to us in this life, different from what a man, or such a limited being, would, beforehand, expect from a very powerful, wise, and benevolent Deity? It must be strange prejudice to assert the contrary. And from thence I conclude, that however consistent the world may be, allowing certain suppositions and conjectures, with the idea of such a Deity, it can never afford us an inference concerning his existence. The consistence is not absolutely denied, only the inference. Conjectures, especially where infinity is excluded from the Divine attributes, may perhaps be sufficient to prove a consistence, but can never be foundations for any inference.
There seems to be four circumstances, on which depend all, or the greatest part of the ills, that molest sensible creatures; and it is not impossible but all these circumstances may be necessary and unavoidable. We know so little beyond common life, or even of common life, that, with regard to the economy of a universe, there is no conjecture, however wild, which may not be just; nor any one, however plausible, which may not be erroneous. All that belongs to human understanding, in this deep ignorance and obscurity, is to be sceptical, or at least cautious, and not to admit of any hypothesis whatever, much less of any which is supported by no appearance of probability. Now, this I assert to be the case with regard to all the causes of evil, and the circumstances on which it depends. None of them appear to human reason in the least degree necessary or unavoidable; nor can we suppose them such, without the utmost license of imagination.
The first circumstance which introduces evil, is that contrivance or economy of the animal creation, by which pains, as well as pleasures, are employed to excite all creatures to action, and make them vigilant in the great work of self-preservation.
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But a capacity of pain would not alone produce pain, were it not for the second circumstance, viz. the conducting of the world by general laws; and this seems nowise necessary to a very perfect Being. It is true, if every thing were conducted by particular volitions, the course of nature would be perpetually broken, and no man could employ his reason in the conduct of life. But might not other particular volitions remedy this inconvenience? In short, might not the Deity exterminate all ill, wherever it were to be found; and produce all good, without any preparation, or long progress of causes and effects?
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If every thing in the universe be conducted by general laws, and if animals be rendered susceptible of pain, it scarcely seems possible but some ill must arise in the various shocks of matter, and the various concurrence and opposition of general laws; but this ill would be very rare, were it not for the third circumstance, which I proposed to mention, viz. the great frugality with which all powers and faculties are distributed to every particular being. [...]
The Author of Nature is inconceivably powerful: his force is supposed great, if not altogether inexhaustible: nor is there any reason, as far as we can judge, to make him observe this strict frugality in his dealings with his creatures. It would have been better, were his power extremely limited, to have created fewer animals, and to have endowed these with more faculties for their happiness and preservation. A builder is never esteemed prudent, who undertakes a plan beyond what his stock will enable him to finish.
The fourth circumstance, whence arises the misery and ill of the universe, is the inaccurate workmanship of all the springs and principles of the great machine of nature. It must be acknowledged, that there are few parts of the universe, which seem not to serve some purpose, and whose removal would not produce a visible defect and disorder in the whole. The parts hang all together; nor can one be touched without affecting the rest, in a greater or less degree. But at the same time, it must be observed, that none of these parts or principles, however useful, are so accurately adjusted, as to keep precisely within those bounds in which their utility consists; but they are, all of them, apt, on every occasion, to run into the one extreme or the other. One would imagine, that this grand production had not received the last hand of the maker; so little finished is every part, and so coarse are the strokes with which it is executed. Thus, the winds are requisite to convey the vapours along the surface of the globe, and to assist men in navigation: but how oft, rising up to tempests and hurricanes, do they become pernicious? Rains are necessary to nourish all the plants and animals of the earth: but how often are they defective? how often excessive? Heat is requisite to all life and vegetation; but is not always found in the due proportion. On the mixture and secretion of the humours and juices of the body depend the health and prosperity of the animal: but the parts perform not regularly their proper function. What more useful than all the passions of the mind, ambition, vanity, love, anger? But how oft do they break their bounds, and cause the greatest convulsions in society? There is nothing so advantageous in the universe, but what frequently becomes pernicious, by its excess or defect; nor has Nature guarded, with the requisite accuracy, against all disorder or confusion. The irregularity is never perhaps so great as to destroy any species; but is often sufficient to involve the individuals in ruin and misery.
[210]
On the concurrence, then, of these four circumstances, does all or the greatest part of natural evil depend. Were all living creatures incapable of pain, or were the world administered by particular volitions, evil never could have found access into the universe: and were animals endowed with a large stock of powers and faculties, beyond what strict necessity requires; or were the several springs and principles of the universe so accurately framed as to preserve always the just temperament and medium; there must have been very little ill in comparison of what we feel at present. What then shall we pronounce on this occasion? Shall we say that these circumstances are not necessary, and that they might easily have been altered in the contrivance of the universe? This decision seems too presumptuous for creatures so blind and ignorant. Let us be more modest in our conclusions. Let us allow, that, if the goodness of the Deity (I mean a goodness like the human) could be established on any tolerable reasons a priori, these phenomena, however untoward, would not be sufficient to subvert that principle; but might easily, in some unknown manner, be reconcilable to it. But let us still assert, that as this goodness is not antecedently established, but must be inferred from the phenomena, there can be no grounds for such an inference, while there are so many ills in the universe, and while these ills might so easily have been remedied, as far as human understanding can be allowed to judge on such a subject. I am Sceptic enough to allow, that the bad appearances, notwithstanding all my reasonings, may be compatible with such attributes as you suppose; but surely they can never prove these attributes. Such a conclusion cannot result from Scepticism, but must arise from the phenomena, and from our confidence in the reasonings which we deduce from these phenomena.
[211]
Look round this universe. What an immense profusion of beings, animated and organized, sensible and active! You admire this prodigious variety and fecundity. But inspect a little more narrowly these living existences, the only beings worth regarding. How hostile and destructive to each other! How insufficient all of them for their own happiness! How contemptible or odious to the spectator! The whole presents nothing but the idea of a blind Nature, impregnated by a great vivifying principle, and pouring forth from her lap, without discernment or parental care, her maimed and abortive children!