History of philosophical pessimism
Giacomo Leopardi

The sense of the nothingness of all things, the inadequacy of each and every pleasure to fill our spirit, and our tendency toward an infinite that we do not understand comes perhaps from a very simple cause, one that is more material than spiritual. The human soul (and likewise all living beings) always essentially desires, and focuses solely (though in many different forms), on pleasure, or happiness, which, if you think about it carefully, is the same thing. This desire and this tendency has no limits, because it is inborn or born along with existence itself, and so cannot reach its end in this or that pleasure, which cannot be infinite but will end only when life ends. And it has no limits (1) either in duration (2) or in extent. Hence there can be no pleasure to equal (1) either its duration, because no pleasure is eternal, (2) or its extent, because no pleasure is beyond measure, but the nature of things requires that everything exist within limits and that everything have boundaries, and be circumscribed.
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