Determinism

A Christian Apologist insists I am a "rigid determinist" because I consider free will to be an illusion. If a label is required to define my views on free will then I would suggest "compatibilist" or "probabilist".  But then again, there are many types of determinism.

I will start by trying to summarise my perspective on determinism. Eventually I will expand this to provide an overview of types of determinism...  

1 Summary 

I don't believe the universe is deterministic because I believe (a) not everything that happens is completely determined by prior events and (b) there are multiple (perhaps infinite) possible futures. So for example, if it were possible to rewind the universe back to its original state and restart the Big Bang process, we would end up with a different, albeit similar, universe.

However it is a fact that many events can be predicted, but only to a certain level of probability - the weather is a good example which I will use later, as I don't think anyone would suggest the weather has free-will.   So rather than seeing the universe as deterministic, I think a better word is probabilistic.  However, any discussion on determinism is complicated because there are many types of determinism and I will discuss those later.

So let's apply this to what we know of the brain. Empirical evidence shows that moments before we are aware of what we will do next, our brain has already determined what we will do. We then become conscious of this “decision” and believe that we are in the process of making it.  So the brain determines what we will do, but the brain is not "deterministic" because we can't predict with certainty what decision it will come to - the decision the brain makes can't be completely determined by prior events. Influenced, yes, but not determined.    Maybe my brain will cause me to eat that delicious hot fudge sundae on the menu, maybe it won't.  All we do know is that the decision, whatever it is, was made by my brain before I was conscious of the decision.   

A Religious Apologist might argue that if brain processes can be described by biology and chemistry then they must be deterministic because the actions of atoms and molecules can be absolutely determined. In fact they can't, because we know the subatomic world is probabilistic. The Religious apologist might then argue that the weather and the brain appear to be probabilistic but that's just because they are very complex.  It would then follow that in the distant, deterministic future,  an "omniscient" computer could be built which will be able to predict the weather across the planet for years into the future, and therefore a similar computer could determine a person's actions from when they are born to the day they die just by calculating the trajectory of their molecules.  I don't think any of that is possible because it is not just the complexity that makes determination of events difficult. The real reason is that at the most fundamental level, physical processes are subject to quantum-mechanical unpredictability and randomness, whether it's in the brain or in DNA or in the planet's atmosphere.  

So now randomness has entered the explanation, does that mean our thoughts would have to be random if they are the result of probabilistic, sub-atomic processes? No it doesn't. The inherent quantum randomness of matter results in probable outcomes, not random outcomes.  A good analogy is a lottery where the jackpot winner picks 6 number between 1 and 49. The chances of winning are 14 million to one - which is almost zero. But every week, at least one person wins on average, because over 14 million tickets are sold. 

If we know a lot about someone's life and history and experiences, and if we have studied what they've said and what they believe, and if they are of sound mind, then we can make a good assessment of how they will behave and the choices they will make - but not with 100% certainty.  When we say we "know how someone thinks", we are assessing how their brains are "programmed".  But the brain is "re-programmed" every second of every day so although we can make a good guess as to whether they will, for example, eat a hot fudge sundae within the next 10 minutes, perhaps they will experience something tomorrow which will put them off hot fudge sundaes for the rest of their lives. 

2 The definition of determinism 

For this I turn to the excellent book "Free Will: The Scandal in Philosophy" by Bob Doyle. 

"Determinism is the idea that everything that happens, including all human actions, is completely determined by prior events.  There is only one possible future, and it is completely predictable in principle, most famously by Laplace’s Supreme intelligent Demon, assuming perfect knowledge of the positions, velocities, and forces for all the atoms in the void.

More strictly, I strongly suggest that determinism should be distinguished from pre-determinism, the idea that the entire past (as well as the future) was determined at the origin of the universe. 

Determinism is sometimes confused with causality, the idea that all events have causes. Despite Hume’s critical attack on the necessity of causes, and despite compatibilists’ great respect for Hume as the modern founder of compatibilism, many philosophers embrace causality and determinism very strongly.

Some even connect it to the very possibility of logic and reason. And Hume himself believed strongly, if inconsistently in necessity. “‘tis impossible to admit any medium betwixt chance and necessity” he said.  Bertrand Russell said “The law of causation, according to which later events can theoretically be predicted by means of earlier events, has often been held to be a priori, a necessity of thought, a category without which science would not be possible.”  

But some events may themselves not be completely determined by prior events. This does not mean they are without causes, just that their causes are probabilistic. Such an event is then indeterminate. It might or might not have happened. It is sometimes called a “causa sui" or self-caused event. But a probabilistically caused event may in turn be the adequately deterministic cause for following events. These later events would therefore not be predictable from conditions before the uncaused event. We call this “soft” causality. Events are still caused, but they are not always predictable or completely pre-determined."

3 Types of Determinism

Again, from the excellent book "Free Will: The Scandal in Philosophy" by Bob Doyle. 


Actualism is the idea that only whatever actually happens could ever have happened. It denies the existence of alternative possibilities for actions. This idea began with the logical sophistry of Diodorus Cronus’ Master Argument for determinism. Statements about a future event that are true today necessitate the future event.

Sophisticated defenses of this idea include the so-called Frankfurt cases, which claim that an agent’s actions can be free even if a hypothetical intervening controller can change the agent's decisions, preventing any alternative possibilities that might have appeared as what John Martin Fischer calls “flickers of free-dom”.

Behavioral Determinism assumes that our actions are reflex reactions developed in us by environmental or operant conditioning. This is the Nurture side of the famous Nature/‘Nurture debate - note that both are determinisms. This view was developed to an extreme by B. F. Skinner in the early 20th century, who had great success “programming” the behaviors of animals, but never with perfect control of behavior. Many cognitive scientists are behaviorists who see the mind as a computer that has been programmed, by accident or deliberately, by education, for example.

Biological Determinism finds causes for our actions in our genetic makeup. This is the Nature side of the Nature/Nurture debate. Again, both sides are determinisms. There is little doubt that our genes pre-dispose us to certain kinds of behavior. But note that our genes contain a minuscule fraction of the information required to determine our futures. Most of the information in the adult brain is acquired through life experiences.

Causal Determinism assumes that every event has an antecedent cause, in an infinite causal chain going back to Aristotle’s Prime Mover. Nothing is uncaused or self-caused (causa sui). Galen Sttrawson supports this view with his Basic Argument. Note that there are always multiple causes for any event. Basically,
all the events that are in the past light-cone of an event can have a causal relationship with the event. 

Cognitive Science Determinism results from a computational model of mind that sees the mind as a computer. The mind may be evolving its own computer programs, but the overall process is completely pre-determined, say cognitive scientists, and philosophers like Daniel Dennett.

Fatalism is the simple idea that everything is fated to happen, so that humans have no control over their future. Notice that fate might be an arbitrary power and need not follow any causal or otherwise deterministic laws. It can thus include the miracles of omnipotent gods, and thus be a theological fatalism. Some philosophers use the term fatalism loosely to cover other determinisms. Richard Taylor’s well-known article, Fatalism, in the Philosophical Review was about logical arguments denying future contingency. The Idle Argument claimed that since things are fated, it is “idle” to take any actions at all, since they can have no effect. 

Historical Determinism is the dialectical idealism of Hegel or the dialectical materialism of Marx that are assumed to govern the course of future history. Marxists have often felt they could revise the past to suit their purposes, but claimed that the future is economically determined.

Logical Determinism reasons that a statement about a future event happening is either true or it is not true. This is the Principle of Bivalence and the Law of the Excluded Middle. lf the statement is true, logical certainty then necessitates the event. Aristotle’s Sea Battle and Diodorus Cronus’ Master Argument are the classical examples of this kind of determinism. If the statement about the future is false, the event it describes can not possibly happen. In logic, as in other formal systems, truth is outside of time, like the foreknowledge of God. Fortunately, logic can constrain our reasoning, but it cannot provide us with knowledge about the physical world nor can it constrain the world.

Linguistic Determinism claims that our language determines (at least limits) the things we can think and say and thus know. The Sapir-Whorf hypothesis claims that speech patterns in a language community constrain the conceptual categories of a linguistic community and thus determine thought.              

Mechanical Determinism explains man as a machine. If Newton’s laws of classical mechanics govern the workings of the planets. stars, and galaxies, goes the argument, surely they govern man the same way. Note that although Rene Descartes described human bodies and all animals as deterministic machines, he said that the human mind was free and undetermined (indetermiriata).

Necessitarianism is a variation of logical and causal determinism that claims everything is simply necessary. This was Leucipus’ view at the beginning of determinism. This was the most popular name for determinists in the 18"‘ century, when they were opposed to libertarians.

Neuroscientific Determinism assumes that the neurons are the originators of our actions. “My neurons made me do it.” The Libet experiments have been interpreted to show that decisions are made by the brain’s neurons significantly before any action of conscious will.

Nomological Determinism is a broad term to cover determinism by laws, of nature, of human nature, etc.

Physical Determinism extends the laws of physics to every atom in the human mind and assumes that the mind will some day be perfectly predictable, once enough measurements are made. The paradigmatic case is that of Laplace’s Demon. Knowing the positions, velocities, and forces acting on every particle in the world, the demon can know the entire past and future. All times are visible to such a super intelligence.

Psychological Determinism is the idea that our actions must be determined by the best possible reason or our greatest desire. Otherwise, our acts would be irrational. Since all the possible actions are presented to the mind, determined by prior actions, the choice is not really made by the agent.

Pre-determinism claims that everything that ever happens was pre-determined at the beginning of the universe. Theological predestination is similar, but if God is assumed to be omnipotent, the events may have been pre-destined more recently. Some theologians insist that God is unchanging and outside of time, in which case predestination reduces to pre-determinism.

Religious or Theological Determinism is the consequence of the presumed omniscience of God. God has foreknowledge of all events. All times are equally present to the eye of God (Aquinas’ totem simul). Note the multiple logical inconsistencies in the idea of an omnipotent, omniscient, benevolent God. If God knows the future, he obviously lacks the power to change it. And if benevolence is assumed, it leads to the problem of evil.

Spatio-temporal Determinism is a view based on special relativity. The “block universe” of Hermann Minkowski and Albert Einstein is taken to imply that time is simply a fourth dimension that already exists, just like the spatial dimensions. The one possible future is already out there, up ahead of where we are now, just like the city blocks to our left and right. J.J.C. Smart is a philosopher who holds this view. He calls himself “somewhat of a fatalist."

Finally, Compatibilism is the idea that Free Will is compatible with Determinism. Compatibilists believe that as long as our Mind is one cause in the causal chain then we can be responsible for our actions, which is reasonable. But they think every cause, including our decisions, are pre-determined. Compatibilists are Determinists. Although some modern compatibilists say they are agnostic on the truth of determinism (and indeterminism).

Some of these determinisms (behavioral, biological, historical-economic, language, and psychological) have demonstrable evidence that they do in fact constrain behaviors and thus limit human freedom. But others are merely dogmas of determinism, believed primarily for the simple reason that they eliminate random chance in the universe.

Chance is anathema to most philosophers and many scientists. But without indeterminacy, there are simply no possibilities for the world to be different from what these many determinisms claim that it will be. 

4 Taxonomy of Determinism

The "family tree" of determinism shows how determinism is not black and white.   

From Bob Doyls aka The Information Philosopher

Illusionism 

llusionism is the position that free will does not exist and is merely an illusion. Many ancient and modern thinkers have made this claim. They have usually been strong determinists, from Hobbes to Einstein. Classical compatibilists, from Hobbes and Hume on, have held that free will exists but that it is compatible with determinism (actually many determinisms).

Since the discovery of irreducible quantum mechanical indeterminism, most scientists and some philosophers have come to understand that determinism is a dogmatic belief unsustainable from the evidence.

It is strict determinism that is the illusion. Quantum mechanics suggests that all physical processes are statistical, and all knowledge is only probabilistic. Hence strict determinism is an illusion

The Valerian Model
Faniel Dennett is a compatibilist and argues for a two-stage model of free will named"Valerian" after the poet Paul Valéry, who was influenced by Poincaré's two-stage approach to problem solving, in which the unconscious generates random combinations. In his book The Psychology of Invention in the Mathematical Mind, Hadamard quoted Valéry...

It takes two to invent anything. The one makes up combinations; the other one chooses, recognizes what is important to him in the mass of things which the former has imparted to him.

Although Valery describes two persons, this is clearly William James's temporal sequence of random chance ("free") followed by a determining choice ("will"). For James, chance and choice are part of a single mind. So perhaps this two-stage mind model is better named "Jamesian" free will.

Dennett makes his version of a two-stage model very clear, defending it with six reasons. However, Dennett remains a compatibilist.


Libertarianism
(Not to be confused with political Libertarianism i.e. the movement promoting individual liberty and minimised government)

Libertarianism says humans are free from all forms of determinism and that freedom seems to require some form of indeterminism. "Radical" libertarians believe that one's actions are not determined by anything prior to a decision, including one's character and values, and one's feelings and desires. This extreme view, held by leading libertarians such as Robert Kane, Peter van Inwagen and their followers, denies that the will has control over actions.

A more modest libertarianism has been proposed by Daniel Dennett and Alfred Mele. They and many other philosophers and scientists have proposed two-stage models of free will that keep indeterminism in the early stages of deliberation, limiting it to creating alternative possibilities for action.

Most libertarians have been mind/body dualists who, following René Descartes, explained human freedom by a separate mind substance that somehow manages to act in the physical world. Some, especially Immanuel Kant, believed that our freedom only existed in a transcendental or noumenal world, leaving the physical world to be completely deterministic.

Religious libertarians say that God has given man a gift of freedom, but at the same time that God's foreknowledge knows everything that man will do.

Incompatibilism

Incompatibilism says determinism is incompatible with human freedom. It is a complex idea, because it is not committed to the truth or falsity of determinism. It was invented by Peter van Inwagen as a new free will position that denies the truth of "compatibilism." It is an "anti-compatibilism" that is more subtle than the question of the existence of free will or determinism.

Hard Incompatibilism

Hard incompatibilists think both free will and moral responsibility are not compatible with determinism.  

5 Do the Laws of Physics Deny Human Freedom?

Of all the determinisms listed above, physical determinism stands out as a special case.

All the fanciful logical, theological, and nomological determinisms described here are basically just ideas.

Isaac Newton’s classical mechanics was also an idea at first, of course, just a theory. But then it was confirmed experimentally, by observations that have grown more and more accurate with every passing decade.

To be sure, the theory has been revised and refined, first for the case of matter moving at velocities that are a significant fraction of the speed of light. Albert Einstein’s special theory of relativity goes beyond classical mechanics, but it asymptotically approaches the classical theory as velocities go to zero.

The next grand refinement was Einsteins general theory, but it too corresponds to ordinary Newtonian physics in the limit.

The most important refinement is the quantum mechanics of Werner Heisenberg and Neils Bohr. Again, it corresponds to the classical theory, in the limit of large numbers of particles.

When Arthur Stanley Eddington revised his 1927 Gifford lectures for publication as The Nature of the Physical World, there he dramatically announced “It is a consequence of the advent of the quantum theory that physics is no longer pledged to a scheme of deterministic law.” There is nothing in the laws of physics, or any wider “laws of nature”, that in any way puts constraints on human freedom.

...and then along came neuroscience...

6 The Evidence from Neuroscience

Any discussion on determinism, especially in the context of free-will,  has to take account of observations of physical phenomena. Experiments show that prior to the conscious intention to perform an action, unconscious brain activity which causes the movement  (the “readiness potential”) is detectable by EEG recordings.  In other words, your brain appears to decide to move before any conscious intention to do so, suggesting that the conscious decision “I choose to move” is an afterthought - not the cause. Things are already set into motion long before any conscious awareness of that decision is made. For more about free will go here