Determinism and the Laws of Nature

The “Laws of Nature” are a metaphor for the reliable patterns of behavior that science observes in the objects and forces that make up the physical universe. In the physical sciences we find Newton’s laws of gravity and motion, plus many others contributed by other scientists.

But the notion is not limited to physics. Any science that observes reliable patterns of behavior in the objects they study may also use the notion of “laws”, “principles”, or “rules” to describe those patterns. For example, economics speaks of the law of supply and demand, and psychology speaks of the principles of human behavior.

The notion of a “law”, “principle”, or “rule” implies something that governs behavior. But the planets and stars do not consult a law book to determine what they ought to do. It is only a metaphor. The laws of nature simply describe how things appear work, based upon repeated empirical observations in nature and in laboratory experiments.

The only behavior that the Laws of Nature actually control is that of the scientists who use these rules to predict what is likely to happen under certain circumstances. For example, NASA scientists used the formula for gravity to map the trajectory of the Voyager 1 and Voyager 2 space probes as they passed near each planet.

The Laws of Nature have no causal powers. They are descriptive, not causative. But something causes the Earth to reliably orbit the Sun. If not an external set of laws, then what is it?

The cause is found in the objects themselves. The mass of the Sun and the mass of the Earth have a mutual gravitational pull toward each other. The inertial force of the Earth’s current trajectory counterbalances that pull, resulting in the annual orbit. The objects (Earth and Sun) and forces (gravity and inertia) are actually causing the orbit. The laws of physics merely describe how to calculate the effects of the forces upon the objects.

Clarity on this point is essential to understand what determinism does and does not mean. A familiar description of determinism is found here in the Stanford Encyclopedia of Philosophy’s article on “Causal Determinism”:

“Causal determinism is, roughly speaking, the idea that every event is necessitated by antecedent events and conditions together with the laws of nature.”

And a little later this:

“Determinism: The world is governed by (or is under the sway of) determinism if and only if, given a specified way things are at a time t, the way things go thereafter is fixed as a matter of natural law.”

But the author himself points out the metaphorical nature of these “laws” in section “2.4 Laws of Nature”, where he says this:

“In the physical sciences, the assumption that there are fundamental, exceptionless laws of nature, and that they have some strong sort of modal force, usually goes unquestioned. Indeed, talk of laws “governing” and so on is so commonplace that it takes an effort of will to see it as metaphorical.”

So, why is this distinction between a metaphor (the “Laws” of Nature) and an empirical description (an orbit caused by two masses, gravitation, and inertial motion) important? It is important because, like the Earth and the Sun, we also happen to be natural objects that go about causing things to happen.

If we attribute our behavior to the Laws of Nature, rather than our own nature, it gives the false impression that we have no control over what we choose to do, but are instead forced, by this imaginary external legal system, to do its will rather than our own.

The incompatibilist version of determinism, referred to inexplicably as “hard” determinism, pushes the fatalistic message that we have no control over our lives. All the important causes of our choices came before we were even born. It denies us any causal agency, suggesting instead that we are only along for the ride, and that something other than us is in the driver’s seat. And what is in the driver’s seat? The metaphorical laws of nature!

For this brand of determinism, the metaphorical view replaces the empirical view, and the imagination replaces objective observation. The result is not a “hard” determinism, but a false determinism. Any version of determinism that blinds itself to a whole class of causal agents is incomplete, and offers only a false version of reality.

To avoid this error, any true version of determinism must acknowledge human causal agency. Human causal agency includes events called “choosing”, where we consider multiple options, evaluate how they might turn out, and then choose what we will do. This choosing operation is usually the most meaningful and relevant cause of our deliberate actions.

And we call this event “free will”. The term refers to the fact that our will, our specific intent for the immediate or distant future, was freely chosen by us. By “freely chosen” we mean that the choice was not imposed upon us by coercion or other forms of undue influence, such as deception, mental illness, hypnosis, etc.

In summary, to understand determinism correctly, we must avoid viewing the laws of nature as some external causal agent that necessitates events. The laws of nature are a metaphor, they are not real. Only the objects and forces that make up the physical universe are real. Only they can cause events. We happen to be among those real objects. The events we deliberately cause effect our intent. It is within these events of choosing that we find free will in the natural universe.


For more details on the nature of Determinism, see “Determinism: What’s Wrong and How to Fix It“.