Life As No One Knows It

The Physics of Life’s Emergence

What is Life?

Physics, as we collectively understand it at this moment in history, provides a fundamental description of a universe devoid of life. It’s not the universe I live in, and I bet you don’t live there either.

If Vitalism Is Dead, Maybe You Are Too

Our universe is weird when you start to understand it (in fact, it gets odder the more you think you understand it)

The real physics underlying life might be even stranger still. While right now we do not understand what principles govern life, they may one day be as obvious to subsequent generations as the curvature of space-time or the existence of particles of light (photons) are to us now.

What modern science has thought us is that life is not a property of matter. Physicists and chemists see very intimately what the rest of us who think life exists cannot: there is no magic transition point where a molecule or collection of molecules is suddenly “living”. Life is the vaporware of chemistry: a property so obvious in our day-to-day experience - that we are living - is noneexistent when you look at our parts. If life is not a property of matter, and material things are what exist, then life does not exist. This is probably the logic Andy was going for. Yet here we are.

The Paradox of Defining Life

One of the most popular definitions for life circulating in scientific communities is that “life is a self-sustaining chemical system capable of Darwinian evolution.”

A lot of people use this definition and like it. But at the same time, like all definitions for life, it fails to deliver on solving the hardest problems. It has not allowed use to prove a mechanism for the origin of life nor design new instruments to search for and measure the presence of alien life on another world.

Why Life?

[…] physics is a way of approaching the world by developing abstract descriptions of nature that possess, in their abstraction away from the every-day objects of our experience, the highest explanatory power. In this book we are after a theory with high explanatory power that will provide new, deeper insights into the nature of life. Incidentally, the fact that explanatory theories work in physics, and science more broadly, is itself an important clue into the nature of life. Life is, after all, the only kind of physical system we know of that can write down explanations like the laws of physics.

In these laws, entropy is a way of measuring how disorderly things are. You can also think of it as a measure of the unavailability of energy for doing useful things.

For living things to, well live, they need to harness energy from their environment - that is, they need to eat and then be able to metabolize what they have eaten to turn it into energy and biomass. The banana bread I had for a snack this afternoon is currently being metabolized in my stomach as I type this. This in effect decreases the entropy of my environment, creating more order instead of disorder. Because acquiring energy in this way is so central to what life must do to persist, many have confused this with what life is.

By contrast cities, are the direct consequence of evolutionary processes that began on Earth more than 3.7 billion years ago, with the gradual acquisition of information leading to the emergence of what we call cellular life, multicellular life, societies with language, and eventually the artifacts of those societies that we call cities.

Cities do not spontaneously fluctuate into existence because a disequilibrium exists; they require a long causal chain of events - a lineage as I’ll describe throughout this book - for the universe to construct the. The memory that leads to the construction of a city is acquired over eons via selection; it is not spontaneously self-organized in space, but instead assembled across time.

From Atoms to Agents

Phil’s central argument claimed that while we can reduce the components of the universe to elementary building blocks, and in turn describe these by reasonably simple laws (the edifice of the last four hundred years of physics), this does not imply that we can reconstruct the universe form those laws alone. Each new scale - moving up from elementary particles to atoms to chemistry to biology to technology - might have its own fundamental rules or laws not fully reducible to the lower levels.

Personally, I am convinced there is entirely new physics in the living universe (the part of reality that includes living things), awaiting our discovery.

To get to an answer for “What is life?“we may need to ask a different question: “Why life?” That is we must transition from defining life based on a set of descriptors possibly unique to our Earth, to deriving life’s properties from a fundamental theory of the kind physicist are known for developing, which not only explains what but also why.

Natural Kinds

[…] there are major and abrupt transitions - paradigm shifts - that open new approaches to understanding the world that scientists would not have considered valid in earlier generations.

Yet given how attempts to define life based on common sense criteria have so far failed, it may be our best shot. I also find it hard to believe that quantum physics and theories of gravity reveal deeper aspects about the fundamental nature of reality than life does: life is after all the only part of the universe we know of that can comprehend the rest, including writing down these theories of physics. Surely that warrants an explanation that is equally as deep as quantum physics or relativity, if not deeper.

Hard Problems

Three great problems that plague scientists and philosophers alike are the origin of matter, the origins of life, and the origin of mind.

But problems that are conceptually hard are quite different because they require paradigm shifts and demand entire new ways of thinking - we cannot just apply the old rules to the new problems. There are many conceptually hard problems in science. What is intelligence? Can we make conscious machines? How will the universe end? Why do we exist? Is immortality possible?

In fact many of us working on the origin of life now feel it is precisely the hard problem we need to solve in order to understand the technological transitions we are currently living through: Many of our technologies appear to be taking on a life of their own, extending our biological lineages into new substrates, right before our eyes.

The Hard Problem of Consciousness

What I am experiencing - being surrounded by pink blooms, the desert breeze, the ephemeralness of the moment -neuroscientists and philosophers will call qualia. Qualia is the word we use to label and talk about what we all seem to feel in our mental states rendering something, or nothing, or anything at all: it is the felt quality of being.

The Hard Problem of Matter

I cannot know any more of what it is like to be an electron than I can of what it is like to be you. Perhaps science cannot resolve this. Personally I think I have a better idea of what it is like to be you than what it is to be an electron. Even the idea that it “is like” something to be an electron feels hard to comprehend. But experiencing electrons are an important consequence of on of the proposed resolutions to the hard problem of consciousness: perhaps consciousness is fundamental, and therefore all matter is conscious.

You might naively think that the electron really does have a mass, a charge, and a spine, and that these are intrinsic properties of the electron. But these properties can also be considered to merely describe how electrons interact with certain measuring devices.

In fact, we will never have complete information about any object that exists in our universe, because we can never know about an object without it interacting with another (e.g., at some point the interaction must involve a measuring device). We do not know what it is for any object to just be. This is the hard problem of matter, first coined by the philosopher Galen Strawson in a New York times article. It points to how we are challenged to understand what is physical, because understanding anything that exists outside of measurement is deeply problematic.

It is important to keep in mind as a theory builder that whatever you assume as the axioms in your mathematics, or fundamental in your theories of physics, constrains and in many ways determines your subsequent reasoning and worldview. It defines the boundary of what you can explain.

Both the hard problem of consciousness and that of matter seem intractable to answer in our current scientific framework.

Instead of asking what consciousness is, we ask: What does consciousness do?

But here we are not measuring whether something has experience (what consciousness is), but instead whether something that has experience can do different things because it has an internal world (what consciousness does).

So we need to ask, does anything in the universe exist that might not be possible if subjective inner worlds did not exist? The answer, I think, is yes. There are things like rockets, which existed within our collective imagination for centuries before they were ever built as physical objects with definite properties. There is nothing about rockets that violets the laws of physics in our universe. But at the same time, rockets do not form spontaneously anywhere in the universe, because they require specific knowledge to build them. That rockets can be made to happen, once minds emerge that can imagine them, is a nontrivial feature of our universe. Rockets are physical evidence of imagination. Rockets are not special in the regard; many thins in the human environment are evidence of the inner world of the human mind: computers, cars, houses, gardens, fashion, etc.

Some things that exist are imagined through abstraction (are counterfactual) and become physical (made actual) through a phenomenon deeply connected to what we call consciousness is potentially a window into the mechanism for bringing specific configurations of matter into existence across time.

In the words of Albert Einstein, attributed to an interview with The Saturday Evening Post in 1929:

I am enough of the artist to draw freely upon my imagination. Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.

The Hard Problem of Life

S 51.