“An argument which proves too much, proves nothing.” ~M.M. Mangasarian
Carl Popper popularized the concept of scientific falsifiability. He asserted that a hypothesis, proposition, or theory is observably valid only if it is falsifiable. This criteria has become a fundamental test of scientific validity. Here’s Wikipedia’s definition:
Falsifiability or refutability of an assertion, hypothesis or theory is the logical possibility that it can be contradicted by an observation or the outcome of a physical experiment. That something is "falsifiable" does not mean it is false; rather, that if it is false, then some observation or experiment will produce a reproducible result that is in conflict with it.
Causality, as a proposition, states that every material effect must have an adequate antecedent cause. This is a falsifiable scientific principle, easily proven by observation or experiment.
Determinism, as a proposition, states that for everything that happens there are conditions such that, given them, nothing else could happen. This is a philosophical assertion that is not scientifically falsifiable for complex organisms, like humans (as opposed to inanimate objects): it can not be proven by observation or experiment. However, it is falsifiable for inanimate objects.
This distinction between inanimate objects and animate beings is often overlooked (i.e. ignored) by hard determinists. They would have you believe that physics recognizes no causal difference between a brain and a rock: that both are just collections of atoms controlled by causality in exactly the same way. They, in effect, deny possession of their own minds and with foolish certainty sacrifice common sense to the altar of physics.
Knowledge is a relatively safe addiction; that is, until it becomes idolatry. Certainty is an illusion. It's not determinism versus free will; one or the other. That's a false dichotomy. There are other possibilities: ones you're likely to miss if you take the wrong approach. And hard determinists are taking the wrong approach. The fact is, physics is concerned with the inanimate universe. Biology is concerned with animate life. Physics deals with simple inanimate objects. Biology deals with complex animate organisms and beings. Physics is amazing and glamorous . . . but it's the wrong discipline to apply to the question of free will.
Eugene Wigner was a Hungarian-American theoretical physicist and mathematician. He won the Nobel Prize in Physics in 1963 for “his contributions to the theory of the atomic nucleus and the elementary particles, particularly through the discovery and application of fundamental symmetry principles". Wigner is important for having laid the foundation for the theory of symmetries in quantum mechanics as well as for his research into the structure of the atomic nucleus. Wigner is also important for his work in pure mathematics, having authored a number of theorems.
In his famous and thought-provoking essay, “The Unreasonable Effectiveness of Mathematics in the Natural Sciences”, Wigner mentioned the inanimate nature of physics 5 times:
Note, in particular, that last one (#5). The possibility of understanding the many phenomena of life is a far-off dream and far from assured compared to the progress we've already made in physics. Biology deals with animate, phenomenal, complex systems. Physics (everything else) deals with inanimate, physical, matter/energy . . . not because of some arbitrary classification but because they are fundamentally divergent.
The difference between physics and biology is an important one. Any single cell in your body (of which there are over 200 kinds) includes more processes and performs more functions than any single inanimate object in the universe. Furthermore, our bodies contain more of these cells than The Milky Way contains stars -- and that doesn't even take bacteria into consideration. We are complex systems of complex systems. Animate beings (most notably, humans) are unlike anything else in the universe and dwarfs the inanimate universe in complexity.
Reciprocal causation (a.k.a. feedback) is a fundamental principle of biology found in many processes such as epigenetics and neurophysiology. With reciprocal causation, an action is both cause and effect (Richard C. Francis, Epigenetics, page 124). It is not limited to biological phenomena and, contrary to intuition, is not a violation of causality. Reciprocal causation (I’ll use the word, feedback, from here on out) is central to complex systems and their emergent phenomena such as consciousness and life itself.
Here’s how Wikipedia defines feedback:
Feedback is a process in which information about the past or the present influences the same phenomenon in the present or future. As part of a chain of cause-and-effect that forms a circuit or loop, the event is said to "feed back" into itself. Ramaprasad (1983) defines feedback generally as "information about the gap between the actual level and the reference level of a system parameter which is used to alter the gap in some way", emphasizing that the information by itself is not feedback unless translated into action.
Conscious intelligence is not “all in the brain” – it’s an amalgam of feedback between 3 components: the brain, sensory organs and environment. If you never had any one of these 3 components, you could never develop consciousness or intelligence.
Triadic reciprocal causation is a term introduced by Albert Bandura to refer to the mutual influence of feedback between three sets of factors: personal (e.g., cognitive, affective and biological events), the environment and behavior. He groups the brain and sense organs under “personal factors” (which also include experience and genetics) but the interplay between brain, sensory organs and the environment are still maintained. Because of triadic feedback, our behavior influences the environment, dynamically altering it – as it alters us – in a perpetual feedback loop.
How accurately any of this reflects reality is a matter of opinion. We simply don’t know enough about the brain to understand even simple processes – much less complex ones like self-aware intelligence or free will. What it suggests to me is that trying to explain biological processes with physics is like trying to observe the moon with a microscope. You need the whole picture: not a narrow focus. The material reductionism of physics is the wrong approach to a complex system; and the human brain is the most complex system in the universe. A neuron may be amenable to physics but a brain is not. Physics can certainly make contributions to neuroscience but, overall, the brain and its attendant phenomena are the purview of biology, not physics.
What I do know is that the central role of feedback, in life, introduces myriad opportunities for the emergence of amazing phenomena unlike anything else in the inanimate universe: abiogenesis, reproduction, regeneration, replication, respiration, digestion, circulatory and other autonomous systems, motility, reflexes, instincts, epigenetics, sensory perception, symbiosis, immunology, evolution, consciousness, intelligence and, yes, free will.
Just because the brain is deterministic at the microscopic scales of physics does not mean it must also be so at macroscopic scales. It's not surprising that the potential for emergent phenomena driven by dynamic feedback systems are so easily missed (or dismissed) by the physicist’s narrow focus – a case of not noticing the forest for the trees. Emergent phenomena is a fact of nature -- life itself is a an emergent phenomena -- and the feedback-rich systems of the brain are fertile grounds for emergent phenomena like consciousness, intelligence and imagination: why not also free will (choice)?
The hard determinist’s insistence that free will violates causality and/or determinism is a false dichotomy stemming from the misapplication of physics to biological processes. There are other possibilities. I think the dynamic process of intelligent feedback produces reciprocal causation and enables choice by making our thoughts both cause and effect. Reciprocal causation, is a non-linear mode of causality in which an action can be both a cause and an effect: a dynamic feedback loop that feeds off of itself, like Uroboros: the ancient Egyptian mythological serpent, swallowing its own tail. Such a process is ripe for producing the emergent phenomenon of free will, despite the false dichotomies of physical reductionists who reduce thought to neuronal activity.
If you make the scientifically unfalsifiable claim that free will is impossible because brain activity is causally deterministic at microscopic scales (molecular or neuronal), then your linear thinking is really painting yourself into a corner because ALL brain activity (like memory and reason) are causally deterministic at microscopic scales. If you thus consider free will impossible, then so is reason. And if reason is impossible, how do you know anything at all? That’s just nuts. Remember, an argument which proves too much, proves nothing. I’m suspicious of, and dissatisfied with, any scientifically unfalsifiable claim – particularly one that talks me out of possession of my own mind.
It is with feedback that we are self-aware. Feedback provides context. Feedback informs our decisions. Consciousness and intelligence are impossible without mental feedback. We may not yet be able to prove it but I think reciprocal causation offers plenty of potential for free will to emerge from intelligent feedback – just as surely as consciousness and intelligence do. I mean, it seems like a minor feat compared to conscious intelligence. We are self-determined and responsible for our actions. We are far from puppets on strings.