“But against the palpably sophistical proofs of Leibniz that this is the best of all possible worlds, we may even oppose seriously and honestly the proof that it is the worst of all possible worlds. For possible means not what we may picture in our imagination, but what can actually exist and last. Now this world is arranged as it had to be if it were to be capable of continuing with great difficulty to exist; if it were a little worse, it would be no longer capable of continuing to exist. Consequently, since a worse world could not continue to exist, it is absolutely impossible; and so this world itself is the worst of all possible worlds.

Thus throughout, for the continuance of the whole as well as for that of every individual being, the conditions are sparingly and scantily given, and nothing beyond these. Therefore the individual life is a ceaseless struggle for existence itself, while at every step it is threatened with destruction. Just because this threat is so often carried out, provision had to be made, by the incredibly great surplus of seed, that the destruction of individuals should not bring about that of the races, since about these alone is nature seriously concerned. Consequently, the world is as bad as it can possibly be, if it is to exist at all. Q.E.D.”

– Schopenhauer, The World as Will and Representation, Vol. II, Ch. 46.