This blog post originated from a discussion with physicist Karo Michaelian about his book Thermodynamic dissipation Theory of the Origin and Evolution of Life. The difference between physics and biology is a topic that deserves a blogpost. It will be an informal discussion.
If organisms are just physical objects and must obey the laws of physics, what biological laws could exist? Physicists explained the Universe. Physicists have finally arrived at The Theory of Everything which explains all known physical phenomena in the universe from the smallest to the most massive things . And organisms are in between. If organisms are physical objects, they are also explained by The Theory of Everything. They should also obey physical laws. But then, do we need Darwin? Do we need Mendel? Do we need Watson & Crick? Could the biology department be subsumed in the Physics department and send biologists home? Let's listen to a physicist:
" ...the biologists simply are not trained to think in terms of symmetries and fundamental laws, as physicists are. (...) Biologist want simple answers that can be written out in a single paragraph, with learning as little mathematics as possible, and they found one in the perspective of Darwin (and, of course it is a perspective and nothing more). It works as a nice description for some things, but it is only a poor description of reality and misses completely at understanding the fundamental function of life. The physicist wants to know what is behind this Darwinian description and this thermodynamic view opens a completely new paradigm with a much richer and profound understanding." Karo Michaelian, August 12, 2020
No wonder that physicists –in possession of the Theory of Everything– want to invade and occupy the territory of biology. As if it were a war. There is only one real science. The usefulness of mathematics for physics is easily explained. Physics deals with dead things. Dead things behave rather predictably. They are being moved by external forces. Newton! The movements of the planets! . But living objects move themselves. In a way that cannot be predicted by physics. How come?
The first difference between physics and biology:
complexity. There are only 118 chemical elements, but millions of
biological species. The chemical elements do not vary, except
radioisotopes which behave predictably. Humans have DNA with 3.5 billion
bases. All humans differ genetically. There are 67.3 million
single-nucleotide polymorphisms in the human population . A
human body has millions of cells, each cell contains in total 42 million
protein molecules. The majority of proteins exist within a narrow range
- between 1000 and 10,000 molecules. Some are outstandingly plentiful at
more than half a million copies, while others exist in fewer than 10
molecules in a cell . And these are only proteins. Physics has no
laws for this huge amount of complexity. Physics studies dead and simple
A hot cup of tea (source)
A hot mouse (Apodemus sylvaticus) ©GK
Most importantly, physicists don't understand the difference between a mouse and a cup of tea. A mouse maintains a temperature difference between its body and the environment. A cup of tea also has a higher temperature than its environment. But what happens with the cup of tea? The temperature difference has gone within an hour. Just obeying the laws of physics. The mouse maintains the temperature difference all its life. Physical laws don't explain the difference in behaviour between a cup of tea and a mouse. Physics cannot explain how the physical object called 'mouse' maintains its temperature. This example alone suffices to suggest that we need a separate science. It's called biology, the science of the living things.
Does a mouse maximize heat loss? Being naked would help! That would very
likely maximize heat loss . Heat loss may be a driving force in the
abiotic and pre-biotic world. But living organisms have subsystems that
control energy uptake, energy production, energy use, energy
storage, and heat loss . Those systems by-pass physical laws without
violating them. Just as birds and air-planes do not violate the law of
In the living world, energy is under control, it is regulated: thermo-regulation. Because it is under control, pure physical laws cannot be applied. Therefore, physical laws cannot be the driving force of evolution.
Yes, physical laws constrain the properties of living organisms,
but within those constrains there is freedom to shape organisms. And
what a shapes there are! Endless forms most beautiful! Heat loss occurs
in living organisms, but it is not a driving force, certainly not
the driving force. Energy management is one of the fundamental
differences between biological and physical systems. This is under
genetic control. Genetics is information . The control of
chemical and physical processes is the main difference between living
and physical systems , . It is part of the definition of life.
I add two important reasons why organisms have energy control systems:
- without energy control they die. Energy uptake is not maximized, but optimized.
- organisms can produce more offspring if they use energy more efficiently. That's the evolutionary reason.
Organisms that are less energy efficient waste energy and cannot invest
as much energy in reproduction because that's an energetically very
costly process. In general: energy efficient organisms, especially animals, out-compete less
energy efficient organisms. Energy efficient organisms are winners,
energy wasters are losers . Warm-blooded animals have fat, fur or
feathers to prevent heat loss. Whales, dolphins, seals and other marine
mammals can generate their own heat and maintain a stable body
temperature despite fluctuating environmental conditions. But these
animals take thermoregulation to an extreme, enduring water temperatures
as low as –2 degrees Celsius and air temperatures reaching –40 degrees C
. They have biological inventions that oppose heat loss. That's
against the Thermodynamic Dissipation Theory. Life is a
successful fight against the Second Law of Thermodynamics,
against disorder, against equilibrium
. There is certainly no attempt to lose as much heat as
possible. That would be insane .
|Dead Weasel Mustela nivalis ©GK|
Even a dead weasel is not quite a dead physical object as can be seen
on the picture above. It is teeming with life. Flies are the first
organisms to occupy the unfortunate animal. Many follow, including
bacteria, worms, beetles, fungi, maybe a fox or a raven .
So, if physicists are blind and deaf for the differences between living
and dead objects, no useful exchange of ideas between physicists and
biologists will happen. Arrogance and ignorance will be deadly for any
communication. Only as equal partners in science we will understand
- A cell holds 42 million protein molecules, Science daily January 17, 2018
- I wrote about that in my review part 2 of Thermodynamic dissipation Theory.
- See further 'Not Wasting Energy' in my review part 2. 16 May 2018.
- For more details see: Open Questions / Genetic variation in this review.
'Processes in living systems must be regulated and controlled' is one
of 5 Real (absolute) life criteria. See my
Ganti review. In engineering it is known as: Control Theory. Heat production in a 'warm-blooded' animal is regulated. Otherwise the animal would be overheated and die. The heat is generated by Brown Adipose Tissue. On the other hand, in some animals their metabolic rate and body temperature drop during the night to conserve energy (torpor). To conserve energy! Regulation! Control!
- Information is the difference between life and matter, A review of Hubert Yockey's 'Information theory and molecular biology'. Yockey is a physicist.
- How do marine mammals avoid freezing to death? Scientific American, 13 May 2009.
- Thousands of unexpected microbes break down our bodies after death, Science, Dec. 10, 2015
- If not maximize and not minimize heat loss (minimize heat loss is against TDT), than anything goes? Any value would be compatible with the Thermodynamic Dissipation Theory? But then it would be unfalsifiable! The theory would not forbid anything. It would not predict anything. It would not say one thing about the world. It would make the TDT non-empirical and theory-less. Worst of all: no mathematics involved! That's a serious matter. 14 Aug 2020 15:09
- A friend of mine, Frank Visser, uses this illuminating metaphore: life behaves like a sailboat sailing into the wind. A sail boat has the ability to move forward despite being headed into the wind. Life is also sailing against The Second Law of Thermodynamics dictating that order becomes disorder. 21 Aug 2020;
- In a comment Karo Michaelian wrote "Almost all physicists agree that we have discovered all of the fundamental laws of nature needed to begin an attempt at describing complex systems through these formalisms, both living and non-living systems. We do not need new laws." I would like to see how Michaelian derives Mendel's laws from physical laws! 23 Aug 2020
- Newton ignored the composition of the planets, the elements, the temperature, the composition of the atmosphere. In short: everything geologists, biologists and climatologists are interested in. Newton used abstract planets. Furthermore, physicists use 'ideal gas' or 'perfect gas' (an ideal gas is a theoretical gas composed of many randomly moving point particles that are not subject to interparticle interactions); a point particle is an idealization of particles heavily used in physics: it lacks spatial extension; being dimensionless, it does not take up space. So, even dead things are often too complicated for physicists! 27 Aug 2020
- To save energy animals go into hibernation or torpor. Some hummingbirds in South America go into torpor: a state of reduced metabolic activity and temperature that is not unlike hibernation, but only one night long. (Nature) 11 Sep 2020
- Ernst Mayr (2004) What makes Biology Unique? Considerations on the autonomy of scientific discipline. (a defence of the autonomy of biology). See my summary.
- Stuart Kauffman (2019) A World Beyond Physics: The Emergence and Evolution of Life. Stuart Kauffman is a theoretical biologist. Especially relevant is: Beyond Law: Biology Cannot Be Reduced to Physics in chapter 11.
Postscript 25 Aug 2020
After writing this blog I discovered the views of theoretical biologist Robert Rosen:
The wikipedia page contains a rather detailed description of his theories about living systems and how they differ from physical systems. His book Life itself (2005) is still available at amazon. Large parts can be read at google books.
"By proposing a sound theoretical foundation for studying biological organisation, Rosen held that, rather than biology being a mere subset of the already known physics, it might turn out to provide profound lessons for physics, and also for science in general".