Things happen because they are likely, even with self-organization

When we observe that living beings (including humans and their economy) are self-organizing occurrences, i. e. their continued existence depends on regularly lowering entropy within themselves, this could be understood to mean that living beings were in some sort of permanent struggle against ever-increasing entropy. However, a newer theory, called Maximum Entropy Production, says that they in fact further net entropy. The reasoning is that even though living beings lower entropy in their bodies, they thereby generate so much entropy in their environments that in total, there is more entropy in the universe than if they weren’t around. See for example:

1. Kleidon, A. Beyond Gaia: thermodynamics of life and earth system functioning. Clim. Change 66, 271–319 (2004).
2. England, J. L. Statistical physics of self-replication. J. Chem. Phys. 139, 121923 (8pp) (2013).
3. England, J. L. Dissipative adaptation in driven self-assembly. Nature Nanotech 10, 919–923 (2015).

Or this more recent comprehensive analysis: Endres, R.G. Entropy production selects nonequilibrium states in multistable systems. Sci Rep 7, 14437 (2017)

It’s simple to think of examples for that. Let’s compare a rocky surface with the same surface being covered by plants. With the bare surface, sunlight would hit it and only a small part would be absorbed and turned to heat (thereby increasing the entropy of the universe a bit). The rest of the light would be reflected back into space. But if there are plants, they will absorb a lot of the light to fuel photosynthesis. Not only is this an inefficient process which immediately loses the majority of the absorbed light to heat, even the remainder, which is stored as chemical energy and used to lower the entropy within the plants’ bodies, will eventually turn to heat when the plant is eaten, dies or discards material (like leaves) which then decays. Compare that with the alternative, where the reflected sunlight might have traveled through space for millennia at least, not increasing the entropy of the universe much, and you will easily see that the presence of life increased the entropy of the universe.

Living beings are not the only systems for which the ability to consistently lower entropy within them has been observed. For example, the atmospheres of Earth, Mars, and Titan (a moon of Saturn) transition between regular states far from thermodynamic equilibrium (which would be the state with most entropy within the system). Similarly, hydrological processes on land, i. e. how water dissipates through the Earth’s soil, is far from such an equilibrium. Maximum entropy production can also account for that, and it lends strength to the theory that you can find it in more aspects of nature than just in life. We can call all these processes self-organizing according to Postulate 6 since they achieve states that are ordered, i. e. organized, instead of ending up with random chaos.

In all these cases, it is not necessarily the most likely event that happens, because all of this is still based on stochastics. But the law of large numbers makes sure that only things that are very close to the highest likely event can possibly happen. So, it at least will get very close to maximum entropy production all the time.

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