Determinism

[gL.edu] This article gathers contributions by Rosa Lyubovitskaya, developed within the context of the Conceptual clarification about "Information, Knowledge and Philosophy", under the supervisión of J.M. Díaz Nafría.

Determinism, the idea that every event is determined by past events based on the natural laws, has caused an important philosophical and scientific debate for a long time, leading to the following questions: "Is the universe fundamentally deterministic, meaning that every single event in the universe has already been predetermined billions of years ago? Do we really have free will the way we think we do, or are all events, including our own actions, merely the inevitable consequences of prior causes?"

This paper examines these questions by first defining the term from different viewpoints, including the concepts of causality, logic, theology, and the idea that free will can exist in a deterministic world.

Throughout history, different views on this question were documented by many philosophers and scientists. Some of them are presented in this paper:

Isaac Newton, who formulated the fundamental laws of physics, believed in a deterministic world, governed by those laws, while David Hume, believing free will can coexist with determinism, and Immanuel Kant, who believed in free will, both opposed determinism, asserting it would undermine moral unaccountability in humans. James Williams also leaned against determinism, stating it would deem the concept of regret meaningless.

Arguments for and against determinism are provided using not just philosophical insights, but also interdisciplinary topics, such as neuroscientific brain experiments and experiments in the field of quantum mechanics, providing insights into modern science and provoking new questions, while encouraging the reader to reach his own conclusion on determinism.

Finally, the paper discusses the implications determinism would have on the concepts of information and knowledge, posing the question, whether determinism would make our pursuit of truth and understanding inauthentic, as, in the absence of free will, it would be impossible to independently obtain or question given knowledge.

Etymology

The word "determinism" comes from the latin verb "determinare" and translates to: define, establish, calculate, set out, cause, bring about and decide (Wiktionary contributors, 2023).

Definitions

Determinism: According the article about free will, determinism can be defined as the idea that every event that will happen in the future is fully determined by events from the past and the natural laws.

Free Will (Indeterminism): Again referring to the article about free will, free will (also called indeterminism) refers to having the full control to independently decide, which actions to carry out. In other words, free will can be described as "a significant kind of control over one’s actions” (O’Connor & Franklin, 2022), as cited in the article.

Causal Determinism: The idea that every event is caused by previous events and conditions, along with the natural laws that govern them, implying that all actions and decisions are the result of prior causes (Hoefer, 2023).

Logical Determinism: The idea that all propositions (statements), including those about the future, must be either true or false. This means that the truth or falsity of statements about future events is already fixed, even if those events have not yet occurred (Vihvelin, 2022, under “1. Preliminaries”).

Theological Determinism: The idea that an omniscient God exists, who knows about the truth or falsity of all propositions, including those about the future, leading to the question of how free will can exist when God already infallibly knows all that is going to happen (Vihvelin, 2022, under “1. Preliminaries”).

Compatibilism: As explained in the article about free will, compatibilism is the idea that determinism is fully compatible with free will, and also that the freedom or abscence of freedom of an action is defined independently from its determination or causation, but by whether the action is caused by the person in question itself or another person or circumstance. Moreover, compatibilism states that causation and determination are a necessity for free and responsible action (Russell, 2020).

Incompatibilism: The idea opposite to compatibilism, claiming that determinism is incompatible with free will.

Philosophers and Scientists on Determinism

Isaac Newton

Newton's fundamental laws, formulated back in 1687, imply that the behaviour of all matter in the world is governed by universal patterns, making him a supporter of the idea of determinism:

“I. Every body continues in its state of rest or of uniform rectilinear motion, except if it is compelled by forces acting on it to change that state.

II. The change of motion is proportional to the applied force and takes place in the direction of the straight line along which that force acts.

III. To every action there is always an equal and contrary reaction; or, the mutual actions of any two bodies are always equal and oppositely directed along the same straight line.“

(Scheck, 2018, p. 2)

David Hume

As one of the founders of classical compatibilism, David Hume claims that both determinism and free will coexist (Russell, 2020, under “1. ‘Liberty and Necessity’ – The Classical Reading”).

As a consequence of determinism, Hume questions religion by claiming that all evil in the world would thus be directly attributed to God, and not the individuals performing the acts of crime, making them completely morally unaccountable for their actions (Russell, 2020, under “6. Free Will and the Problem of Religion”).

Immanuel Kant

The existence of freedom, which according to Kant is necessary for our ability to make judgements based on ethics and apply reason directly opposes the idea of determinism. “Reason creates for itself the idea of a spontaneity that can, on its own, start to act–without, i.e., needing to be preceded by another cause by means of which it is determined to action in turn, according to the law of causal connection, Kant says” (as cited in McCormick, n.d., under "8.a. – Kant’s Ethics: Reason and Freedom").

Kant claims that our ability to reason and follow a framework of ethical rules gives us a choice and hence makes us ethically responsible for our actions, unlike animals whose actions, due to the lack of reason, are just a result of causality and determination, which removes all ethical accountability from animal predators (McCormick, n.d., under "7.b – The Idea of Reason: Reason and Freedom").

William James

While claiming that he cannot prove or disprove free will, William James believes in indeterminism based on his own practical point of view, which states that the assumption of determinism would render the regret of bad life events completely pointless and thus, unlike the pessimists, optimists and subjectivists, perhaps being able to accept that, he himself could not live with it.

Though he admits that determinism is logically possible he rejects it pragmatically as unacceptable.

Furthermore, he posits that for people to accept and act on basic moral concepts, it requires them to believe in their ability to use free will and freely influence their environment (Pomerleau, n.d., under "6.a. – Freedom and Morality – Human Freedom").

David Lewis

As a materialist and determinist, David Lewis believes that the evolution of this world from any given point in time, given the laws of nature and the state of the world at that time, is determined, if the past, along with the laws of nature, is fixed.

Following the idea of possibilism, he assumes the existence of possible worlds, almost like causally isolated parallel universes, each of them fully deterministic.

David Lewis rather supports compatibilism, while also acknowledging the position of incompatibilism in the context of the problem of evil and free will ("David Lewis," n.d.).

Arguments supporting Determinism

Neuroscience: Decisions as Biochemical Processes in the Brain

An experimental study conducted by Benjamin Libet, Curtis A. Gleason, Elwood W. Wright and Dennis K. Pearl investigated the buildup of electrical activity in the brain, called the "readiness potential", that occurs before a person executes a motion, caused by their own will rather than by reflexes or external stimuli.

When comparing the point in time of the readiness potential and the moment the person becomes aware of their decision to move, the findings showed that the brain activity, inducing the motion, preceded the person's awareness of their intention to move by at least several hundred milliseconds (Libet, Gleason, Wright & Pearl, 1983).

This means that a free, voluntary act, can be initiated by the brain before the person itself is aware of their own free decision to perform that motion, which directly challenges the idea of free will.

Many critical questions about the idea of free will are posed by these results: Is it merely an illusion our brain makes us believe in, after already having determined the next action without actually giving us a free choice?

These results suggest that our "decisions" might just be the aftermath of biochemical processes in the brain, devoid of individual choice and hence merely determined by the natural laws.

The split-brain studies conducted by Roger W. Sperry in 1968 and Gazzaniga, as he described in his book "Who's in Charge?" in 2005, suggests that the brain is very much capable of deceiving itself.

The Split-Brain Studies: An Illusion of Free Will?

R. W. Sperry: Foundations

In his paper "Hemispheric Deconnection and Unity in Conscious Awareness", Sperry described his split-brain experiments, in which the corpus callosum, which connects the brain's left and right hemispheres, was severed as a treatment for epilepsy, making both hemispheres function independently from one another (split brain).

With the knowledge that the left hemisphere controlls the right side of the body, and the right hemisphere controlls the left side, including visual processing, he conducted the following experiment:

A word was displayed on a screen for less than a second, being on the left side of the split-brain-participant's field of vision, and then repeating the same process, but instead displaying the word on the right side of the participant's field of view. When the participants saw the word with their right eye, the left hemisphere processed it, enabling him to say the word. However, when he saw it only with his left eye, he was unable to do so, concluding that the left hemisphere is responsible for language-related processing.

In a similar way, Sperry also deduced that the right hemisphere possessed visual and spatial skills.

This important finding helps us to understand the following experiment conducted by Michael S. Gazzaniga on a split-brain-patient:

M. S. Gazzaniga: Ad Hoc Rationalization

Gazzaniga showed a split-brain patient two pictures: a chicken claw (located in his right visual field, processed by his left hemisphere) and a snow scene (located in his left visual field, processed by his right hemisphere). When asked to choose related images, the patient's left hand pointed to a shovel (as appropriate for the snow image), and his right hand pointed to a chicken (as appropriate for the claw image).

When asked why, his left-hemisphere speech center confidently explained: "The chicken claw goes with the chicken," and, regarding the shovel, "You need a shovel to clean out the chicken shed." The left brain, unaware of the snow scene seen by the right brain, fabricated a plausible yet incorrect justification instead of admitting ignorance (Gazzaniga, M. S., p. 133).

This demonstrates that the patient was not aware of the real reason of why he selected the shovel, but instead his left hemisphere made up a false explanation. So the left hemisphere believed in having made a free choice, while instead it was the right hemisphere that made the choice for other reasons (based on visual skills) than the patient believed.

That implies that the patient’s choices were determined by subconscious processes in the brain, which acted independently from conscious reasoning, aligning with the deterministic idea that our actions may be governed by neural mechanisms beyond our awareness, rather than by actual free will.

The fact that the patient's brain generated such a confident yet incorrect justification for his choice, raises significant doubts about whether we can trust our sense of free will, or whether it is merely a post hoc rationalization for us to feel in control of our actions. This also shows that our brains are capable of giving us an illusion of us having control over our actions.

The experiment results can also be seen as a question about consciousness: Who is really making the decisions in our brains? To answer the question of whether human choice is deterministic, one has to also clear whether an unawareness of choice fully negates the idea of free will or not.

Furthermore, subconscious processes in non-split brains, like for example mental health conditions or trauma, impact our decision-making more than we are aware of, making our actions partly pre-determined by the state of our brains.

One could go even further and argue, that from this perspective, our decisions and hence actions must be at least partly deterministic, because a will cannot be considered fully free, if it relies on neural processes that are outside of our direct control.

Challenges of Determinism

The Liar Paradox and Logical Determinism

The Liar Paradox, which is primarily attributed to Eubulides of Miletus, a contemporary of Socrates, challenges the definition of logical determinism, that claims that binary truth values can theoretically be assigned to any proposition, in the past, present or future.

To demonstrate this, we can use the following self-referential sentence:

This sentence is false.

If we try to define this sentence as true, it automatically makes the sentence false, and if we thus assume the sentence is false, the falsity of the sentence must be false, making the sentence, again, true.

This cycle can be continued indefinitely, which directly questions the fundamental definition of logical determinism: In this example, it was not possible to assign a fixed truth or false value to the statement, suggesting that not all propositions may have a fixed truth value.

The Problem of Evil and Theological Determinism

As mentioned earlier, David Hume shows that determinism poses the question of moral responsibility in humans, if God exists as the creator of the world, knowingly having predetermined all processes and actions in said world.

Following the idea of determinism, this would lead to two possible outcomes, according to Hume (Russell, 2020, under “6. Free Will and the Problem of Religion”):

1. Since all human will and action is predetermined by the Creator, all their actions are inevitable and not in their control, leading to the absence of any moral responsibility in humans, and thus making the idea of good and evil meaningless.
2. If despite that, we decide to assign moral responsibility for their actions, it would directly imply that the Creator is just as morally responsible for causing all human actions, including the evil ones, by predetermining them, which then would make him the root of all evil, contradicting the image of a good-willing God pictured in most known religions (Russell, 2020, under “6. Free Will and the Problem of Religion”).

To reach a conclusion about whether the Creator could be blamed for the evil in the world he created it is important to consider that if God was just omniscient and not omnipotent, and if there was theoretically no way to create humankind while also not creating evil, the answer of guilt lies in whether creating humans, allowing the evil to exist, or to refrain from creating humans and evil altogether is the most ethical choice.

Quantum Mechanics and Indeterminism

As described by the wave function in quantum mechanics, individual particles at the quantum level behave probabilistically, and are hence non-deterministic.

This is demonstrated by the Two-Slit Experiment, in which a barrier with two slits is placed between a source of electrons, which are quantum particles, and a screen to display where the electrons end up after being propelled through the double-slit.

When particles are fired one at a time, an interference pattern in form of the wave function appears on the screen, as long as no detectors, determining which slit the particle went through, are present.

When detectors are used, the quantum particles act like classical objects, displaying two clusters on the screen, as we would expect in the macroscopic world (Feynman, Leighton, & Sands, 1963, under "37-4 An experiment with electrons").

One of the surprising insights of this experiment is that observation alone alters the result of the experiment, and also that it directly questions the idea of classical determinism since events at the quantum level are not determined by previous states and hence cannot be predicted or calculated, which introduces indeterminsm.

Richard P. Feynman describes this experiment as "a phenomenon which is impossible, absolutely impossible, to explain in any classical way" (Feynman, Leighton, & Sands, 1963, as cited in S. Goldstein, 2021, 14 June), which emphasizes that the classical deterministic viewpoint cannot explain these results, suggesting indeterminism.

Information and Determinism

Information according to Claude Shannon

As stated in the article about information, Claude Shannon defines information as how surprising a message is to a receiver it is sent to. Shannon quantifies that value of surprise as the amount of reduced uncertainty of the receiver, known as the information entropy (also Shannon entropy).

According to Shannon, the more likely an event is to occur, the lower the informative content of a message that is delivered to the receiver becomes.

In a deterministic world, however, any discussion about the probability of an event occurring would become redundant. Since all events would happen with certainty, there would be no room for alternative events, which would imply that, according to Shannon’s theory, the role of information could be drastically diminished.

How much exactly the concept of information would lose its significance, depends on the receiver's ability to deduce the content of a message independently (by predicting it), relying on his knowledge about natural laws, his logical reasoning and how much he knows about previous events and their causal relationships to the event in question.

In a deterministic world, where humans would have the ability to deduce any event, were given enough data to do so, and would use correct logical reasoning, no amount of information would be obtained from a message about any event, rendering the concept of information, in Shannon's sense, obsolete.

Realistically though, humans would always need at least a basic set of informational statements, which they could use as a starting point to deduce new information based on their own reasoning.

This basic information would represent the fundamental building blocks of the events in the entire universe, fully sufficient to deduce any event at any point in time, if logic was applied correctly. These fundamental blocks would include the first events in the universe, all natural laws and the definition of logic.

Since humans are prone to logical errors, their ability to always predict an event correctly would not be ensured, even given sufficient data. The informational content of a message about an event they failed to deduce correctly, might still be present to a certain level, but would be restricted by the extent of their error.

Also, the average person lacks the scientific expertise to calculate all outcomes of any event as determined by all natural laws. This becomes even harder when we consider the idea of the butterfly effect, as Robert Bishop demonstrated in his article about Chaos, using the following example: " [...] the flapping of a butterfly’s wings in Argentina could cause a tornado in Texas three weeks later." (Bishop, 2024) To predict an event, all small events, such as the flapping of a butterfly’s wings, should be considered carefully, and missing even one small event would lead to a false prediction.

All in all, it can be said, that based on Shannon's idea of information, determinism might limit the presence of real information with a surprise factor, but not fully remove it, because any logic used to predict an event requires premises in the form of knowledge about previous events and natural laws. Furthermore, humans, might misapply their logic, leading to incorrect predictions, and would likely fail to consider all events that are causally linked to their prediction.

Information according to Gregory Bateson

Bateson defines information as a "difference that makes a difference", as stated in the article about information.

We could interpret the "difference" (first word of the definition) as a predetermined causal factor that still results in a noticeable outcome, leading to a difference within the deterministic system, showing that Bateson's definition still applies in a deterministic world.

On the other hand, one could argue that in a deterministic universe, all events follow a fixed causal chain, which means that there are no alternative outcomes or actual differences to the course of events. This would make Bateson's definition about information, if it assumes that the "difference" leads to a real change in the course of events, incompatible with the concept of determinism.

Knowledge and Determinism

To examine the effects a causally deterministic world would have on our knowledge, we need to understand, that under causal determinism, every process in our brains, including the formation of beliefs and the pursuit of knowledge, would also be deterministic, merely caused by biochemical reactions in the brain.

The term "belief" relates to something that we assume to be true, based on our own reasoning and perception, while it may actually be false, as implied in the article about belief.

If it is possible to verify the truth or falsity of a belief, knowledge could be the final step in obtaining truth.

If we define "knowledge" not just as an awareness and understanding of something, as described in the article about knowledge, but also something that is actually true, unlike a belief, which can be false, then the consequences of determinism depend on whether there is only one single objective truth, as stated by realism, or, instead relativism applies, which would mean that there can be multiple subjective truths about one subject:

In the case of Realism, stating that there is an objective reality and the truth or falsity of a statment cannot be influenced by subjective frameworks (culture, beliefs, etc.), determinism would not impact the contents of our knowledge, but rather the selection of it, because only one truth would exist for each proposition, and any real knowledge achieved would be true, as we defined. Whether determinism would exist or not would have no result on the contents of our knowledge.

If instead Relativism were true, meaning that the truth or falsity of all statements depends on a subjective framework applied in order to assess that statment, determinism would not allow any freedoms or alternatives in the contents of our (subjective) knowledge, questioning the autonomy in shaping what we know:

Even in a relativistic view, which might initially seem to offer freedom in knowledge, a deterministic nature of the universe could eliminate our ability to independently obtain or question given knowledge, as all decisions regarding what we consider true would be influenced by deterministic processes governing our brains and external factors.

Conclusion

This paper has examined the issue of determinism and free will by assessing different viewpoints, such as classical philosophy, contemporary neuroscience, and quantum mechanics, also discussing how determinism would affect the idea of information and knowledge.

Shannon's definition of information, as it was concluded, would remain meaningful in a deterministic world, despite a potentially reduced informative content, because all predetermined events would still remain surprising to the receiver of the information if it was unable to predict it correctly, as it would practically often be the case.

If we instead apply Bateson's definition of information, the definition would either remain correct in a deterministic world or would contradict it, depending on how Bateson's definition is interpreted.

When it comes to knowlege, it became clear that determinism would make the process of obtaining knowledge just another event caused by the causal chain of events, minimizing our independence and freedom of arriving to knowledge.

Looking at the viewpoints of different philosophers and scientists, Hume believed that free will and determinism can coexist (compatibilism), Kant argued that free will is fundamental for moral responsibility, Newton believed in a deterministic world ruled by natural laws and James leaned against determinism, stating that a deterministic world would make the concept of regret meaningless.

Furthermore, the neuroscientific field provides insightful experiments, such as Libet’s studies and Sperry's and Gazzaniga's split brain experiments, which challenge the idea of free will by suggesting that decisions may be determined by subconscious processes in the brain, outside of our conscious control, and also that the brain is capable of giving us an illusion of control. If determinism holds true, our actions, beliefs, and decisions could be the result of mere causal chains, leaving us to question the authenticity of our choices.

Opposingly, the double slit experiment conducted in the field of quantum mechanics has introduced the idea of indeterminism, as particles at the quantum level seem to contradict the classical deterministic expectations, instead operating probabilistically.

Also, we showed that the definition of logical determinism doesn't hold true for all statements, because, for example, certain Liar Paradox statements cannot be assigned one truth value.

All in all, answering the question of determinism and free will becomes more and more complex the more viewpoints are considered, so it may remain unanswered, provoking a never ending debate throughout various disciplines.