Decaying universe (credit: XMM-Newton, ESA, NASA, via Wikimedia Commons)

Chapter 14 – The Morally Crucial Features of Modern Physics

At last. We are ready to tackle the moral challenge. The question now is: What are the traits of the real universe, as Science sees it, that should guide how we design our new moral code? Answer: The two most important traits of the modern scientific worldview are entropy and uncertainty. These need a bit more elaboration. 

The laws of thermodynamics say that energy (with matter viewed as a concentrated form of energy) can’t be created or destroyed; it can only be changed in form, as in from chemical energy in gasoline, to heat energy in the cylinders, to mechanical energy in the pistons, the crankshaft, and so on. 

But the laws of thermodynamics also tell us that even though the amount of energy in the universe stays the same, it always flows from areas of greater concentration to areas of lesser concentration. If matter or energy become more concentrated or organized in one area of space, that means an even greater amount energy must flow in from areas nearby. Everything is burning out. Metals corrode, wood rots, people and animals die. Life carries on by struggling against entropy.  

Even the stars and our sun are burning out.  In our everyday experience, this law is the trait of the universe that makes life always hard, always uphill. The physical universe on its own works to kill everything living. 

An area of matter-energy concentration (like our planet or my body) must always be maintained at the expense of even greater rates of energy burnout in nearby spaces. I get energy by eating plants or eating animals which also ultimately depend on eating plants. Plants get their energy from the sun as it burns. When fossil fuels like gasoline are burned, they are releasing stored solar energy, as are hydroelectric dams and firewood. The sun is our source, and it burns and dissipates energy much more intensely than the creatures of the earth get and store second-hand solar energy.

The universe is heading toward a final state in which more than 10⁷⁹ sub-atomic particles will be spread across it at a temperature of absolute zero. We don’t understand numbers that big, but that doesn’t matter. The heat death of the universe, Science tells us, is inevitable. (On the other hand, it isn’t due for over five billion years.) 

To humans, who are energy-concentrated living things, this means that we exist against the natural flow of the physical universe. The level of disorganization or “burnt-outness” of anything (including the whole universe) is called its entropy, and the entropy of the universe is always increasing. This is the first morally significant thing that Physics has to say to Philosophy.