Do you believe in free will? Are you free to choose what you think, say, and do? Or, are your decisions the result of molecular interactions in your body, governed by the laws of physics, over which your control is merely illusory? Democritus (c. 460 – 370 B.C.) was the first to formalize this latter view, called determinism. He and his mentor, Leucippus, “claimed that all things, including humans, were made of atoms in a void, with individual atomic motions strictly controlled by causal laws” leaving no room for free will. He said, “by convention color, by convention sweet, by convention bitter, but in reality, atoms and a void” (via Wikipedia). Aristotle (384 – 322 B.C.), on the other hand, was the first to argue for the former perspective. In The Nicomachean Ethics he “lays out which actions deserve praise and which do not…” suggesting “we are in some way responsible for our actions” (from classicalwisdom.com) and alludes to free will. Shortly thereafter, Epicurus argued that as atoms moved through the void, there were occasions when they would ‘swerve’ from their otherwise determined paths, thus initiating new causal chains. Epicurus argued “that these swerves would allow us to be responsible for our actions, something impossible if every action was deterministically caused” from Wikipedia. Epicurus “did not say the swerve was directly involved in decisions, but, following Aristotle, he thought human agents have the autonomous ability to transcend” (causal laws) from Wikipedia. Philosophers and scientists would go on to debate free will for the next two thousand years, some for, and some against, and continue to do so to this day – with no resolution on the matter…
Figure 1: Bust of Aristotle (384-322 BC), By jlorenz1 – jlorenz1, CC BY 2.5, via Wikipedia
All of us feel that we have control of our choices. You certainly feel you have the power to continue or stop reading this essay if you so choose. It may, therefore, come as a surprise to you to know that many scientists and most physicists think that free will is just an illusion. Generally, they believe that your actions are governed by the laws of fundamental physics, which, in turn, describe the behavior of molecules, which, in turn, describe the behavior of neurons in your brain, which, in turn, determine your behavior. Their rationale can be summarized in the following two points:
First, scientists have been extremely successful at reductionism – finding a simple description of the world where a huge collection of phenomena, from the smallest scales of atoms to the largest scales of the Universe itself, can be explained in terms of a short list of 17 fundamental particles, and just four forces (see “Quantum Fields, the Real Building Blocks of the Universe” by David Tong (2017) for more). Whether we are talking about general relativity (large scale) or quantum mechanics (small scale), predictions of physics equations made long ago continue to be experimentally validated. For example, gravitational waves, predicted by the equations of general relativity in 1916, have recently been detected. They require an enormous four-kilometer-long apparatus, called LIGO, so sensitive it can detect movements of a billionth of a billionth of a meter (). Similarly, the predictions of quantum mechanics have been experimentally validated time and time again. For example, the quantum mechanical prediction of the magnetic moment of an electron has been verified to 11 decimals places (see here for more). Given these foundations, reductionism describes a world in which these rigorous fundamental laws determine the behavior of atoms which determine the chemistry of molecules from which emerge the behavior of biological organisms and so on right up to the entire workings of our own minds – a tree, if you will, with its roots in physics, upon which chemistry and then biology are built. In this video (2013) physicist Sean Carroll likens the emergence of free will to the emergence of temperature in a room full of molecules. No single molecule has a temperature, molecules have kinetic energy, but looked at collectively they do. Temperature derives from the average kinetic energy of molecules. And, temperature is obviously very useful in describing the world around us. Similarly, in this video another physicist, Max Tegmark (2014), compares the emergence of free will to the emergence of the property of wetness from water – no single water molecule has the property of “wetness”, but collectively, water obviously does. The reductionist view is extremely compelling to scientists and receives such widespread acceptance it can feel like dogma.
Figure 2: The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth By MissMJ – Own work by uploader, PBS NOVA , Fermilab, Office of Science, United States Department of Energy, Particle Data Group, Public Domain via Wikipedia
Second, even though living organisms seem starkly different from all the inanimate matter in the reductionist tree, recent experiments in neuroscience have seemingly directly reinforced the reductionist view. In the 1980’s neurologist Benjamin Libet performed experiments on patients (Libet’s experiments) and observed that a “readiness potential” (RP), an EEG based measure of activity, in the motor cortex of the brain was correlated with actions like lifting a finger. The subjects were shown an easy-to-read visualization of a clock (see Libet’s clock here) and were asked to report the time shown when they decided to lift their finger. When the time reported by the subjects was compared with the timing of the readiness potential, it was found the RP increased a few hundred milliseconds before the subject reported making the decision. This suggested that the RP was determining the patient’s actions and, therefore, that their feeling of free will was illusory. More recently, neuroscientists have been able to insert electrodes into the brains of living patients and record the firings of individual neurons – see this TEDx video “Free Won’t” by Moran Cerf (2015). With the electrodes still hooked up to the patient, neuroscientists predict when and which button she will choose to press. The video shows the patient trying to outwit the machine, but it seems to know which button she intends to press before she can do so! (see more in Fried et al. (2010) and Soon et. al. (2008)) Such results suggest that actions might be deterministically predictable, and, if that is true, then there is no room for free will, right?
Still, there is something that feels incomplete about this rational, reductionist, objective description of the world. Perhaps the trouble with it is just that – it is objective! Consider this: even if there is neural activity that predicts simple action, and, even if there are many examples of properties in Nature that emerge, science only offer a description of this deep, rich subjective 1st person experience and this empowering feeling of free will in the 3rd person! The claim that the subjective experience emerges at some point feels arbitrary and trivial. Think about Isaac Asimov’s famous sci-fi novel “I, Robot”. If it was instead named “Wet Robot”, or “Square Robot”, or “Hot Robot”, it just wouldn’t have had anywhere near the same affect! Well, ok, you might have thought for a second about Hot Robot until you realized I was just talking about temperature! All kidding aside, there is a profound difference there. Something much deeper is going on. There are powerful subjective sensual qualities to life’s experiences which simply are not addressed in the scientific framework. Nobel prizing winning physicist, Erwin Schrödinger, in his book ‘What is Life?‘ (1944), had this to say:
“In this chapter I have tried by simple examples, taken from the humblest of sciences, namely physics, to contrast the two general facts (a) that all scientific knowledge is based on sense perception, and (b) that none the less the scientific views of natural processes formed in this way lack all sensual qualities and therefore cannot account for the latter“. – Erwin Schrödinger, What is Life? (1944)
Times have certainly changed regarding physics as the “humblest of sciences”, but Schrödinger’s point is as true today as ever! The reason science can’t say anything about this essential quality of life is as physicist Sean Carol specifically says (here): “we (scientists) realized that we are not smart enough to learn about the world just by thinking about it, we have to go out and look at it”. That’s all well and good for scientific objectivity, but, when we invoke this modus operandi, we are necessarily looking at the world from the 3rd person perspective. Never will you see in a scientific journal articles like: “How it feels when I subject myself to a THz laser“! (although we look forward to this paper: “What is it like to see entanglement?“) Here is Sean debating Alan Wallace, a Buddhist scholar, who charges “introspection plays no role in modern science”: “The Nature of Reality: A Dialogue Between a Buddhist Scholar and a Theoretical Physicist“. Wallace is correct. If we want to understand where our internal, 1st person perspective comes from, and our apparent free will, we are forced to undertake a subjective exploration. That’s not to say we want to abandon the external, objective success of science – we want to supplement it! Can we do both? Suppose we could reconcile the 1st person experience with the 3rd person description of science as dual views of the same thing? That is, suppose it is possible to follow all the laws of physics and have free will…