Naturalism is one of the fundamental tenets of Deleuze's philosophical inspiration. He takes up this theme in his text on ‘Lucretius and the Simulacrum’ (LS, 303–20/307–24), an essay on the Roman philosopher-poet Lucretius (c. 99 BC–55 BC). The central problem of this essay is the role of philosophy: ‘[t]o the question “What is the use of philosophy?” the answer must be: what other object would have an interest in holding forth the image of a free man, and in denouncing all of the forces which need myth and the troubled spirit in order to establish their power? (LS, 314/322). Philosophy imagines what it would mean for man to be free. And in the process it indicts those who would call upon ‘myth’ or the ‘troubled spirit’ to patch up the weak links in the powers-that-be. What does this mean? By the ‘troubled spirit’ Deleuze means anxiety and fear. Crucially, anxiety and fear are not the same as pain. Rather, they are moods in anticipation of a pain which might one day befall. It is when one is forewarned of the possibility of some future pain that one experiences a profound tremulation of the spirit, even though this pain has not yet been seen or felt. Instead, it is precisely because the pain is not yet an actuality that fear and anxiety can proliferate boundlessly. This is precisely the origin of religion and superstition, the shady function of which is then named ‘myth’.

As regards this myth which mass-produces the troubled spirit, Deleuze points out that it is based on the ‘false infinite’. The false infinite is an infinity simply by virtue of its being limitless. And this infinite whispers to us, ‘try as you might, there will always be things you will never understand’, in order to magnify anxiety and fear. However steadfast one's certainties, when this false infinite is preached, one cannot but shudder in an inexorable anxiety. And one who shudders in this way will seek to flee their fear by crying out to power. In turn, those in power will take advantage of this to exercise their rule, and the ruled will wallow in a false contentment, under the illusion that their soul has come to rest. To that extent, those who incite fear and anxiety are the sidekicks of the powers-that-be.