(2) The internal order of organisms is preserved because the disorder produced by their chemical reactions is continuously pumped outside them.
In order to remain alive, in other words, organisms must be in a perpetual state of activity (their cells work even when they sleep), and must continuously pump out the excess entropy of their reactions. In the words of Erwin Schrödinger (1944), they eat not only matter but also order.
Towards the end of the 19th century, in conclusion, a living organism came to be seen essentially as a thermodynamic machine, i.e. as a chemical machine that must be continuously active in order to obey the laws of thermodynamics.

The computer model

Towards the end of the 18th century, just as the chemists’ critique was yielding, another opposition to mechanism arose and gave origin to a new version of vitalism. This movement started as a spontaneous, almost instinctive, reaction of many biologists to a veritable absurdity that mechanists wanted to impose on biology. It was a revolt against preformationism, the idea that adult structures are already preformed in a homunculus within the fertized egg.
In 1764, Charles Bonnet explicitly lanched the great challenge of preformationism: “If organized bodies are not ‘preformed’, then they must be ‘formed’ every day, in virtue of the laws of a special mechanics. Now, I beg you to tell me what mechanics will preside over the formation of a brain, a heart, a lung, and so many other organs?”.
The challenge was clear, and in order to avoid preformationism biologists were forced to conclude that the formative force required by Bonnet in order to account for embryonic development must indeed exist. It was an embryological, rather that a chemical, force, very close to Aristotle’s inner project, but it also was given the name of vis vitalis.
Preformationism, as we have seen, was definitely abandoned in 1828, when Von Baer’s monumental treatise showed that embryonic development is a true epigenesis, as Aristotle had maintained, i.e. a genesis of new structures and not a simple growth of pre-existing structures.