Ancient writers are not usually very forthcoming on the question of what artificial life would be like. This is because most of them think about being alive according to a subtractive logic, such that you just add faculties – or souls, or whatever – to matter and then, as you add more faculties, you turn that matter into a crystal or a plant or an armadillo or a human being. The faculties themselves remain something of a mystery of nature. If this is what life is like, then any attempt to imitate life – by, say, building a working model of an armadillo – is an irrelevancy. However like an armadillo your model might be, it doesn’t have the faculties that would make it alive, so it’s not in any kind of position to be called artificial life.
There are places nonetheless where the kinds of uncanny imitation of life that we worry about nowadays also come to the fore in Greco-Roman literature. One is in Galen, On the Natural Faculties 1.7:
“Taking hold of pigs’ bladders, children fill them with breath and rub them against the ash near the fire – so as to soften but not mar them…While they’re rubbing, they chant certain phrases with meter and song, and all this speech is an invitation for the bladders to grow. After it seems to them to have stretched enough, they blow into it again and stretch it again and again they rub it, and they do all this a number of times, until the bladder seems to them to have reached an adequate stage of growth. But in these children’s works it is clear that, if they increase the magnitude and the internal space of the bladder, it is necessary that they render the body slender by the same amount. If the children were able to nourish away this slenderness, they would change these bladders from small to large in the same way that nature does. But their work is lacking, and it is impossible to bring about growth in imitation of nature not only for children but for anyone else. This is proper to nature alone.”
If Galen explicitly denies that imitation (mimesis) of natural growth is possible, he implicitly concedes that it is: the childish game of blowing up pig bladders would not have struck him as an apt parallel for natural growth unless it were, in some way, actually like that growth. The failure of this imitation is partial, but so is its success. It is like natural growth in one dimension (megethos) but unlike it on another (leptotes).
Galen concludes by positing an absolute difference between the two kinds of growth – one stems from child’s play while the other has its origins in an obscure natural faculty – in a way that does not carry great conviction. If the children – perhaps now wearing masks and lab coats – were also able to add a layer of pluripotent stem cells to the outside of the bladder after each round of inflation, wouldn’t their game now count by Galen’s own standards as a complete imitation of natural growth? The bladder would then be artificially alive, not because it mimicked some living thing or another – after all, there are no pig balloons in nature – but because it possessed a successful imitation of a natural faculty of living things.