Soft determinism, also known as compatibilism, is the belief that determinism is compatible with free will and moral responsibility.

In other words, soft determinism states that even though all events in the world are predetermined by what came before them, it is still possible for people to have free will and thus be morally responsible for their actions.

Soft determinism is one branch of determinism. Determinism is the idea that everything that happens could not have gone otherwise; each event has a fixed outcome because of everything that led to it.

American psychologist and philosopher William James first used the term soft determinism in his essay “The Dilemma of Determinism” (James, 1895).

Soft determinism is a branch of determinism that differs from hard determinism. These branches differ in their views on whether free will is possible in a deterministic universe. Soft determinists believe that free will is possible in a deterministic universe, even when everything is predetermined.

They believe that as long as no external forces force someone to make a certain choice, the person has made a free choice. 

Important Definitions

• Determinism: The philosophy that all events are predetermined, by the chain of events that came before them. 
• Soft determinism/compatibilism: The philosophy that determinism is compatible with the possibility of free will and moral responsibility for one’s actions.
• Hard determinism/incompatibilism: The philosophy that determinism makes it impossible to have free will and moral responsibility for one’s actions.

Examples of soft determinism

Nagel’s example of the peach or the cake

To explain the idea of determinism, philosopher Thomas Nagel (1987) uses an example of choosing between selecting a peach or a piece of chocolate cake out of a cafeteria line.

If you choose the cake and think to yourself, “I could have chosen the peach instead,” what does that mean, and is it true? 

A soft determinist would say that because of some combination of your genetics, your life experiences, your environmental surroundings, and other factors, the fact that you chose the cake was inevitable.

The process of you deciding to choose the cake was just the follow-through of a predetermined conclusion. It is not possible that you could have chosen the peach instead of the cake.

However, you still acted with free will because there was no external force compelling you to choose the cake and not the peach; no one was constraining you or forcing you, and therefore you made the choice freely. 

Another example: To study or to party?

Imagine a Friday night where you have a choice to stay home and study for a big exam on Monday, or to go to a party with friends, and you end up choosing to stay home and study.

A soft determinist would say that this choice was predetermined; you were always destined to choose to study because of some combination of your genetics, how your parents raised you to value education, your knowledge that the exam is very important, and your desire to get a good grade, and so on.

However, even though your choice to study was inevitable, you still acted with free will because your choice was in line with your desires and motivations.

Arguments in favor of soft determinism

Soft determinism relies on a certain definition of the concept of “freedom.” It argues the natural meaning of “freedom” is lack of restraint or compulsion.

Soft determinists argue that when people think about “free will,” they are referring to physical and psychological freedom from being forced to act or constrained into not acting a certain way. They argue that this definition of “freedom” is most intuitive.

Soft determinists argue that given this intuitive definition of freedom, free will is possible under determinism because the only necessary condition for free will is that someone is free from restraint and compulsion.

Even if all of someone’s personality, desires, and motivation may be predetermined by nature and nurture, they can still have free will and make free choices within how they are predisposed to act or think. 

One philosopher who argued in favor of soft determinism was Harry Frankfurt. Frankfurt (1971) argued that people have free will when they have a certain psychological structure; namely, when their first-order desires align with their second-order desires.

Frankfurt defines first-order desire as “what you want,” and second-order desire as “what you want to want.” Someone has free will if what they want aligns with what they want to want.

For instance, if your first-order desire is to go for a walk, and your second-order desire is to want to walk, then your first and second-order desires align, and you are free.

This is how it is possible to be free under determinism: Even though your first and second-order desires may be pre-determined, you are free since they align with each other.

Arguments against soft determinism

Critics of soft determinism generally fall into two categories: those who disagree that determinism is true at all, and those who agree that determinism is true, but disagree with compatibilism and argue that determinism is incompatible with free will and moral responsibility (Strawson, n.d.).

Critics of soft determinism who instead believe in hard determinism argue that the former does not encompass a complete understanding of the nature of determinism and free will. They believe that under determinism, it is impossible to have free will or be morally responsible for one’s actions. 

Hard determinists believe that the soft determinist definition of free will is not sufficient. They believe that the soft determinist definition of freedom is contrived and does not get to the true meaning of freedom. Kant referred to soft determinism as a “wretched subterfuge…, a petty word-juggerly.”

These hard determinists believe that if all of a person’s thoughts, desires, and choices are predetermined by factors often out of their control, then it is impossible to be truly free or morally responsible for their actions.

Besides the hard determinism, there are two additional major schools of thought that disagree with soft determinism: libertarianism, and pessimism.

The libertarianists believe that we have free will, but this is incompatible with determinism, so determinism must not be true.

On the other hand, the pessimists, or no-freedom theorists, believe that free will is impossible, whether or not determinism is true. 

Psychological research on people’s beliefs about free will

Several researchers have investigated the psychology behind people’s beliefs about determinism, free will, and moral responsibility. 

Nichols and Knobe (2007) investigated how the phrasing of questions about these issues affects people’s responses. They found that when they asked people questions about the consequences of determinism in an abstract sense, people’s answers aligned with hard determinism.

For example, if asked, “If everything in the world was predetermined, would it be possible to have free will?” participants often said it wouldn’t be possible. However, when you asked people specific, emotionally-triggering questions about the consequences of determinism, their answers became more aligned with soft determinism. 

Nahmias (2011) shows that hard determinism is unintuitive for average people. The author argues that this evidence provides support in the direction of soft determinism.

The author also provides evidence that when you talk to average people about determinism, they often confuse it with bypassing, a distinct psychological phenomenon in which our minds have no say in our bodies’ choices. 

References

Frankfurt, H. G. (1971). Freedom of the will and the concept of a person. The Journal of Philosophy, 68(1), pp. 5-20. https://doi.org/10.2307/2024717 

James, W. (1896). The dilemma of determinism. In W. James, The Will to Believe and Other Essays in Popular Philosophy (pp. 145–183). Longmans, Green and Co. https://doi.org/10.1037/11061-005 

Nagel, T. (1987). Free will. In T. Nagel, What does it all mean? A very short introduction to philosophy. Oxford University Press. 

Nahmias, E. (2011). Intuitions about free will, determinism, and bypassing. In Robert Kane (ed.), The Oxford Handbook of Free Will: Second Edition. Oxford University Press.

Nichols, S., & Knobe, J. (2007). Moral responsibility and determinism: The cognitive science of folk intuition. Noûs, 41(4), pp. 663-685. https://doi.org/10.1111/j.1468-0068.2007.00666.x