By Stuart Kauffman
In the Nineteenth Century in was common for novels to be serialized in the fine magazines of the day. I propose to use our shared NPR 13.7 space to explore what I hope is an important line of investigation, together with all of you, in a series of posts.
I want to explore two major issues: 1) Is the becoming of the universe entirely describable by natural law? 2) Is the becoming of the universe even entirely due to what Aristotle called "efficient cause"? I think both answers are "No." If so, the universe is open in ways we did not expect.
Since Descartes, Galileo and Newton, we reared in the tradition of Western science, in particular physics, have come to the view that all that unfolds in the becoming of the universe is describable by sufficient natural law.
Buried in our standard world view, most strongly in reductionism in its pure form, are also claims about explanation in science, and often unspoken metaphysical commitments.
I begin with metaphysical commitments briefly. The ancient Greek philosopher, Empedocles, held that what was real was what was Actual in the universe. Einstein's General Relativity holds the same view. What exists for Einstein are "world lines" in a prestated state space, his famous four dimensional spacetime block universe. World lines are "Actuals". World lines just exist. "Time" disappears in General Relativity.
In contrast, Aristotle held that the becoming of the world was a sequence of the Actual begetting the Possible begetting the Actual begetting the Possible. For Aristotle, for Leibnitz at the time of Newton, and for the famous early 20th century mathematician and philosopher, Alfred North Whitehead 23 centuries after Aristotle and 3.5 centuries after Leibnitz, what is "real" in the universe includes both the Actual and the Possible.
Feel your mind going metaphysically a bit numb? Mine does. Just where are these possibles? Under the refrigerator? Can "possibilities" "really be real?" Yet we live with them every day, and venture capitalists invest real money all the time to seize business opportunities. But an opportunity is a valuable Possibility in the future.
We do live with the Possible and we act on it in the real world.
Quantum Mechanics, on the familiar Copenhagen interpretation, and what is called the Born rule, accepted by most physicists, with a more modern "decoherence" version described below, has the famous Schrodinger wave equation. What is "waving" in the Schrodinger equation is either uninterpreted mathematics, or is often interpreted as a simultaneous superposition of all the "possibilities". Then a measurement event occurs and the "wave function collapses" all the possibility waves that can co-exist simultaneously, into a single possibility that is now a "classical" reality, or an "Actual", in the original Copenhagen interpretation.
In a deep sense, in quantum mechanics, interpreted as above, it is Possible (ie quantum) -> Actual (ie classical) -> Possible -> Actual. (Recent evidence suggests that the quantum to classical transition is reversible, hence Possible can transform to Actual and Actual can transform to Possible.)
General Relativity and Quantum Mechanics are often said to be incompatible because the former is a nonlinear dynamical theory, while the latter is a linear dynamical theory. There has been no solution about how to link the two into "quantum gravity". But the above comments about Actual and Possible show that there may also be "metaphysical" commitments that are different in these two pillars of 20th Century physics.
But what could all this have to do with my hope to explore partial lawlessness in the becoming of an OPEN universe?
First, I am coming to doubt that the "co-evolution" of the quantum and classical world is describable by law. The more modern interpretation of the (possibly reversible) transition from the quantum world to the classical world is called "decoherence." It is based on a loss of information about the peaks and valleys of the possibility waves from a quantum system into its environment. Due to this loss, the peaks and valleys of the waves cannot interact and the characteristic quantum interference phenomenon, that I'll describe in a later post, cannot occur.
I will borrow an argument from philosopher Sir Karl Popper to show that in the setting of Einstein's Special Relativity, there can be no "law" for the details of how decoherence happens in any concrete case. This view is contentious, of course. But it seems to be sensible and have experimentally testable consequences. A discussion is available on www.edge.org under my name and "Five Problems in the Philosophy of Mind."
Second, I have already described the evolution of the biosphere by Darwinian "exaptations", (and will again briefly in a later posting), where we cannot prestate all the possible exaptations just for humans in the "Adjacent Possible" of the biophere or econosphere or culture. Then we do not know the sample space of all the possibilities, so can construct no adequate probability measure. Nor can we have natural law for this evolution, if a natural law is, as Nobel physicist Gell-Mann says, a compact description of the regularities of a process. The becoming of the biosphere is partially lawless but not random.
Third, Aristotle had four types of causes: material, formal, final and efficient. The formal cause of a house is the blueprint. The final cause of the house is your decision to build it to live in. The material cause of the house are the bricks and mortar. The efficient causes of the house are the actual processes of constructing the house.
Why should we care? Well, Aristotle also gave us a model of scientific explanation: Deduction. All men are mortal, Socrates is a man, therefore Socrates is a mortal. With Newton and his laws, we mathematized efficient cause as deduction. We use Newton's laws, initial and boundary conditions, say of billiard balls moving on a billiard table, and integrate his equations to compute the trajectories of the balls. But integration is exactly deduction. More, with Newton, Aristotle's other three causes were essentially removed from physics, hence from scientific thought in the West.
And yet: No less a physicist than Stephen Hawking recently wrote an article entitled "Godel and the End of Physics". Why? In the 1930s, logician Kurt Godel proved that mathematics is incomplete. More exactly he proved that from the axioms of arithmetic, there could exist mathematical statements which, if true, were not derivable by deduction from the axioms of arithmetic. These are called formally undecidable statements. And Godel showed that if you added such undecidable statements as new axioms of an enriched axiom set, new undecidable statements would arise - ad infinitum. In short, mathematics has the property that, given an axiom set, not all the true statements given that set are deducible from that axiom set. If explanation is deduction, what does this imply for true statements physics that perhaps cannot be deduced from the laws of physics? Such true physics statements cannot be explained!
So what is Hawking worried about? Precisely that no finite set of laws will suffice to entail by deduction the becoming of the universe, hence "the end of physics". This could imply the end to Nobel physicist Steven Weinberg's "Dream of a Final Theory", a "Theory of Everything" we could write down on a tee shirt.
Suppose Hawking is right! What might be the matter? What does it mean for us if the answer is "No?"
I aim to explore a quite different pathway that depends upon a metaphysics of Possible -> Actual -> Possible -> Actual: Maybe the fault lies in the underlying assumption that all that arises in the universe is due to "efficient causes".
I am finding myself driven to think about opportunities for biological adaptations, and economic innovations. We humans live with such opportunities all the time in real life. Witness the sequence from the invention of the computer to the opportunities to make profit on the personal computer, to Microsoft's opportunity with word processing, then the opportunity to create the world wide web, then the opportunity to sell on the web and eBay, to abundant information on the web, hence Google. New opportunities arise all the time in the evolution of the economy. We seize these opportunities all the time.
But an economic opportunity is a valuable Possibility in the future, so cannot be an Actual efficient cause in the past of an event. Aristotle would say, "These are final causes."
Can evolution create adaptive opportunities, which, as future valuable Possibilities, cannot be Actual past efficient causes, and nevertheless can change the becoming of the universe? I think the answer, carefully considered, is "Yes".
Consider a humming bird and a field of flowers. The bird inserts her beak into the flower to get nectar and feed, but pollen rubs off the flower's stamen onto the sticky beak. The bird flies to the next flower, inserts her beak for nectar and pollen rubs off the beak and onto the stamen of this second flower, pollenating it. This is a mutualism. And it is an "enabling constraint" on the bird and flowers: the "appropriate" behavior of the bird and the existence of its sticky beak, and the "appropriate" synthesis of nectar in the flower are the conditions of one another's very existence in the universe.
This mutualism is a kind of "natural contract" enabling bird and flower to live, if not, die. The evolutionary process blindly stumbled upon the rudiments of this mutualism, and blindly improved both the initial adaptations, and also blindly improved the adaptive opportunity itself to be better mutualists - for example, to achieve the "properly" sticky beak that holds the pollen and the sticky, loose pollen grains on the stamen that rub off onto the sticky beak, but the beak is not too sticky, so pollen rubs off onto the stamen of the next flower, and the pollen is just sticky enough to rub off the beak but hold to that stamen.
For example a flower species might evolve tiny hairs on its pollen, and adjust hair length and glycoprotein sticky material to tune in novel ways the binding to the humming bird beak. Alternatively the pollen might evolve tiny cup structures that hold sticky glycoprotein, and tune the cup size and glycoprotein to tune binding to the beak.
This is the process of evolution blindly finding new opportunities for future adaptations.
But are these different mutualistic adaptive opportunities themselves efficient causes? Opportunities cannot be efficient causes, for they are merely Possibilities, not Actualities, and they lie in the future so cannot be efficient past Actual causes for a present event.
If this is right, evolution of the biosphere, and technology, creates ever new opportunities. These opportunities, if achieved, change the course of the evolution of the biosphere and econosphere, so change the becoming of the universe. But the opportunities are not efficient causes. Then the becoming of the universe is not due only to efficient causes. This may be a response to Hawking: Perhaps we do not need to explain all that happens in the universe as entailed by a finite set of efficient causes mathematized as deduction. Opportunities play a non-causal role in the becoming of the biosphere and economy and history, hence the becoming of the universe.
Finally, future adaptive possibilities become actual realities, which in turn create novel future adaptive possibilities, which become the next Actualities. Possibile -> Actual -> Possible -> Actual in the real evolution of the economy and biosphere.
In short: 1) Is the becoming of the universe entirely "lawful"? No. 2) Are opportunities not causes, yet enable the universe to change how it becomes? Yes.