The popularity of modern naturalism relies on conflating a method with a metaphysics.
The dazzling success of science is used to blind us to the naturalists hidden philosophical assumptions.
Once those assumptions are exposed, metaphysical naturalism is revealed not as the most rational world view, but the dogmatic prejudice of the modern world.
What is metaphysical naturalism?
Metaphysical naturalism is the claim that everything is natural. Exactly what natural means is often vague, but generally it means concordant with the natural sciences.
Regardless of the particular argument the naturalist makes, there is always a slide from science to philosophy. The success of a method is glossed as the truth of a metaphysics. Method naturalism morphs into metaphysical naturalism.
If metaphysical naturalism is true, it means there is no God, no soul, and no afterlife. These aren’t trivial claims; they directly impact the purpose of our lives and our destiny after death. So the question of their truth couldn’t be more important.
We’re often told science has never found anything supernatural, anything beyond nature. Not only has science not found God or souls, it’s also never found evidence of ghosts, fairies, and other magical creatures that aren’t within the domain of physics.
These claims of non-existence go beyond saying science is an effective method for discovering truths about the natural world. They say the natural world is all that exists. The fact that science hasn’t discovered God, souls or ghosts is interpreted to mean those things don’t exist.
It’s not controversial to say science hasn’t discovered all those things; that much is true. But it’s also not surprising, because science isn’t looking for them. The scientific method intentionally excludes certain phenomena from its explanations. It restricts its explanations to the objective and the measurable.
The naturalist scientific method has been overwhelmingly successful. In their exuberance at this success, some people have tried to extend the method and make all our explanations conform to scientific knowledge. This goes beyond appreciating a method, and becomes a philosophical claim.
This philosophy is called by various names, naturalism, physicalism or materialism. These are all variations on the same theme. They say the only things that exist are those things that are revealed by the natural sciences. Materialism says only matter exists. Physicalism says only physical things exist, and naturalism says everything is natural.
These worldviews trade on the prestige of science to support their philosophical claims. They misleadingly suggest that science has proved philosophical naturalism true. The word naturalism is often used indiscriminately to refer to both science and philosophy. First we’re presented with the undeniable success of the natural sciences, and then naturalism magically and invisibly morphs into philosophical claims.
For example, the prominent atheist Richard Dawkins says,
“The universe that we observe has precisely the properties we should expect if there is, at bottom, no design, no purpose, no evil, no good, nothing but pitiless indifference.”
He makes a philosophical claim: the universe has no purpose, no sentience, no good or evil. But who is observing this indifferent and pointless universe? His claim is only true if “we” means “science” and the scientific viewpoint is the only way to observe the world.
We’re so accustomed to hearing statements like this, that we rarely stop to contemplate how peculiar this worldview he’s expressing really is.
Our experience of the natural world
In normal speech, “we” would mean “the humans.” But if we refers to humans with functioning sense organs, the properties we observe when we look at the world aren’t remotely like that. We observe a world full of colours, tastes, sounds, and smells. It’s beauty can often overwhelm us.
We feel a sense of awe and wonder at its harmonic variety and movement. Rather than uncaring, we see how it provides us with all the necessities of life and then goes further and provides us with the ingredients for delights.
Anyone who has immersed themselves in nature doesn’t come away with the Darwinian picture of the world Dawkins expresses. Dawkins describes the nihilistic outlook of the clinically depressed, people suffering from a mental dis-ease.
It’s only if we observe the universe from a strictly scientific viewpoint that it conforms to his description. The scientific method intentionally removes all the subjective properties from its explanations. The fact that good and evil, purpose and indifference aren’t empirical properties that science can measure or detect; doesn’t mean the universe lacks those properties.
But even once we see past the trick and understand the difference between naturalism as a method and naturalism as a metaphysics, we still need to judge the coherence of the metaphysics. After all, no one can deny the success of the scientific method; that’s not in dispute.
Is metaphysical naturalism true?
But what about the merits of the philosophical claim? Does the success of science mean we should extend the scientific viewpoint to everything that exists?
If we want to know if it’s true that everything is natural, the very first thing we need to ask is, What does the word natural mean? What types of things qualify as natural?
And we find that not only is there no clear definition, all attempts to define naturalism fail. Whatever definition we choose results in naturalism being either false or meaningless.
Naturalism’s dilemma
This problem was most famously expressed by the philosopher Carl Hempel and is known as Hempel’s dilemma. The naturalist has two options. If they define natural as based on current physics, then naturalism is false. No one thinks that current physics is complete, and mental properties stand stubbornly outside the realm of physics.
The other option is to say natural is based on an ideal future physics. Now naturalism is vacuous, since no one knows what that ideal physics consists of. The unknown future physics might include souls, gods, fairies and ghosts. With this option, naturalism becomes meaningless. When the naturalist tells us that everything is natural, even they don’t know what natural means.
This problem of incoherence might not seem so pronounced if naturalism were offered as a provisional belief or humble suggestion. But it’s usually delivered with such excessive confidence that anyone who disagrees is deemed guilty of science denial and irrational wishful thinking.
Metaphysical naturalism is a super-natural claim
We’re offered a grand ontological thesis about the entire reality that can’t even define its central term. This is because naturalism isn’t a thesis that starts by observing the world and then logically constructs it’s metaphysics to explain those observations. Instead, naturalism starts with a method of investigating the world and then tries to force reality to fit its chosen method.
Naturalism is a claim that can’t be verified by either science or logic. It goes beyond its own conceptual boundaries to make an extra-natural claim about the whole of reality. It can’t even define itself because nature isn’t a meaningful category of things that exist, its an arbitrary judgement based on a method of investigation.
Naturalism misappropriates the explanatory prestige of science, of method naturalism, and pastes the name on its metaphysics.
Prudence Louise 