Some passages by La Mettrie remind us of the book Ontology of Motion, which argues that Lucretius accentuated that motion is an attribute of matter.
The most important repercussion of this is that motion is natural and does not require gods, spirits, or animating forces outside of nature: nature is “free of masters”, as Lucretius states.
In La Mettrie, in addition to the essential attributes of matter, there is something he called “la force mortice” (the dynamic force), which is “puissance” (power). In page 9, the relation between force and motion is established. This “puissance motrice de la matière” (mobile power of matter) is in every moving body, and it’s impossible not to conceive of these two attributes: that which moves, that which is moved. As we saw in Ontology of motion, the role that this plays is to abolish all supernatural or superstitious animism, and to replace it with the concept of a mechanical nature that exhibits motion on its own according to natural laws.
Against the Theologians
In Histoire Naturelle de l’Ame, La Mettrie closes by echoing Voltaire, saying that there’s no need to fear that philosophers will harm the religion of a country. No, it is the theologians who wish to preside over sects and political parties.
A hundred treatises on materialism are much less to fear than a merciless Jansenist or an ambitious Pontiff.
Nature has no Purpose
One of the features of the anti-creationist view of nature is that nature is blind, mechanical, that it does not “intend” to make this or that machine, this or that body, this organ or that ecosystem. These things appear as a result of random mutations or events, or of the never-ending dance of particles moving in space and relating to each other, and only once their function serves an advantage, do organisms begin to perfect the use of their organs. This argument was originally found in Lucretius.
Nature is blind, innocent, unaware, and in fact this blindness and innocence is a consolation for death.
Pre-Darwinian Naturalist Reasoning
La Mettrie lived prior to Darwin. His Lucretian argument for how humans emerged from the Earth are, therefore, pre-Darwinian, but based on the reasoning that if humans have not always existed, the Earth must have acted as the uterus of mankind.
Why, I ask you, modern anti-Epicureans, why should the Earth, that mother and nurse of all objects, have refused to animal seeds what she allowed to the meanest, most useless and most harmful vegetables?
Obviously, Darwin made huge contributions to our understanding of the evolution of life, and geneticists after him continued his work. But Lucretius demonstrates that the ancients did have an idea of natural selection, and La Mettrie is again writing a commentary on Lucretian ideas when he says:
Perfection was no more achieved in a day in nature than in art.
Art’s fumblings to imitate nature give us an idea of what nature’s fumblings were like.
The idea is that nature produced many anomalies and mutations. Those that were disadvantageous did not survive to pass on their seed, but those that were advantageous did pass on their seed, and after countless generations this produced beings that were increasingly adapted to their environment.
Man “came after” the beasts because man is more complex, therefore man took more time to make.
The case of mutants prove nature’s absent-mindedness and trial by error: her “innocence”, and her lack of intention and of “final causes”. Nature passed by many combinations before reaching the ones that worked effectively. Nature happens to have made eyes, not intending to, just as water serves as a mirror without intending to. He compares this to a metaphor of how chance on a canvas paints something.
Nature’s creation of eyes and ears follows laws of nature similar to the ones that govern the ebb and flow of the sea.
A Glorious Harbor
La Mettrie was deeply aware that much of what he was writing would be considered practically seditious by the religious authorities of his times, and yet he pressed these issues with zeal. We are reminded of chapter 14 of A Few Days in Athens, which closes with the following conclusion concerning the supposed immorality of atheism, originally believed by the character Theon to be a thought-crime. After explaining that it is no crime to believe with certainty in gods, but that’s it’s unreasonable, Wright’s Epicurus closes:
(Let) this truth remain with you: that an opinion, right or wrong, can never constitute a moral offence, nor be in itself a moral obligation. It may be mistaken; it may involve an absurdity, or a contradiction. It is a truth, or it is an error: it can never be a crime or a virtue.
La Mettrie closes his book by beautifully celebrating the breath of fresh air that intellectuals of his time were enjoying as a result of finally being able to openly discuss the anti-clerical ideas that they were entertaining. The Enlightenment had managed to create a “glorious harbor” for intellectuals, and it’s only here that intellectual life had been able to flourish after centuries under the asphyxiating grip of the clergy:
I salute you, favourable climate where any man who lives like others can think differently from others; where theologians do not act as judges of philosophers, a role of which they are incapable; where the freedom of the mind, humanity’s finest attribute, is not chained by prejudices; where one is not ashamed to say what one does not blush to think; and where there is no risk of becoming a martyr to the doctrine whose apostle one is. I salute you, country already celebrated by philosophers, where all those persecuted by tyranny find (if they are deserving and reputable), not a safe asylum but a glorious harbour; where one feels how far the victories of the mind are above all others; where the philosopher, finally crowned with honours and kindness, is only a monster to the minds of the mindless. May you, oh fortunate land, bloom more and more! May you appreciate your good fortune and make yourself worthy in everything, if possible, of the great man who is your King! Muses, Graces, Cupids and you, wise Minerva, when crowning with the most splendid laurels the august brow of this modern Julian — as worthy of governing, as learned, as clever and as philosophical as the classical one — you are only crowning your own handiwork.