3.4.3 - Eliminative materialism

The Eliminativist Problem

Ordinary life seems packed with mental states. You believe the exam starts at 9 a.m., want a coffee, feel anxious, remember a definition, and hope your argument makes sense. Common sense treats these as real inner states that explain what people do.

Eliminative materialism asks a more unsettling question: what if this ordinary way of understanding ourselves is not merely incomplete, but deeply mistaken?

The issue is not whether brains matter. All physicalist theories in this area give the brain a central role. The distinctive eliminativist claim is stronger:

An eliminativist is not simply saying that people use loose everyday language. The claim is ontological: if folk psychology posits inner states such as beliefs and desires, and if those posits fail to map onto what a mature science of the mind discovers, then those posits may be like witches, phlogiston or vital spirits. They were useful in old explanations, but they did not refer to real things.

That is why the theory feels so radical. It threatens not only a philosophical account of mind, but the language through which we explain action, responsibility, self-knowledge and reasoning.

A radical mistake here means a deep error in the basic categories of a theory, not just a few inaccurate details. That is what makes eliminativism eliminative rather than corrective.

The guiding problem is therefore:

If everyday mental concepts help us navigate human life, do they identify real features of the mind, or are they placeholders that a better neuroscience may replace?

Folk Psychology As A Theory

The Churchlands' argument begins with a methodological claim: folk psychology is not just a list of words, but a theory-like framework. It explains behaviour by linking inner states to perception, reasoning and action.

A simple folk-psychological explanation looks like this:

1. Anna wants to drink coffee.
2. Anna believes there is coffee in the kitchen.
3. Anna believes going to the kitchen is a good way to get coffee.
4. Therefore, Anna goes to the kitchen.

This framework is powerful because it lets us move between action, prediction and explanation. If you know someone's beliefs and desires, you can often predict what they will do. If you see what they do, you can often explain it by attributing beliefs and desires.

The eliminativist turns that success into a test. If folk psychology is a theory, then it can be assessed like other theories:

Paul Churchland's section "Why folk psychology might (really) be false" is important because it treats folk psychology as an empirical theory whose success is open to challenge. Patricia Churchland's Brain-wise gives the broader neurophilosophical setting: traditional philosophical concepts of mind should be tested against, and may be revised by, developing brain science.

This does not yet prove eliminative materialism. It sets the terms of debate. If folk psychology is more like an indispensable practice than a theory, then eliminativism loses one route. If it is a theory, and a poor one, then elimination becomes a live possibility.

Reconstruction of the theory-status move:

1. P1: Folk psychology explains and predicts behaviour by positing inner mental states such as beliefs, desires and intentions.
2. P2: A framework that explains and predicts by positing unobserved states is theory-like.
3. Therefore, C1: Folk psychology is theory-like.
4. P3: Theory-like frameworks can be assessed for truth, explanatory power, prediction and integration with other theories.
5. Therefore, C2: Folk psychology may be assessed, and possibly rejected, as a theory of the mind.

Hidden assumption: Everyday psychological practice is sufficiently similar to empirical theorising to be tested in this way.
Inference type: abductive and methodological.
Main pressure point: whether folk psychology is really a theory, rather than a practical interpretive skill or social practice.

The Churchlands' Case For Elimination

Eliminative materialism does not argue from the bare claim that neuroscience is impressive. Its stronger argument is that folk psychology may be the wrong framework for understanding the mind at all.

Paul Churchland's case can be reconstructed like this:

1. P1: Folk psychology is a theory that posits mental states such as beliefs and desires to explain behaviour.
2. P2: A mature science of the mind should retain a theory's posits only if those posits map onto real states or useful successor categories.
3. P3: Folk psychology has serious explanatory failures, limited development, and weak integration with neuroscience.
4. P4: The history of science contains cases where false theories were not reduced but eliminated.
5. Therefore, C1: It is a serious possibility that folk psychology is radically false.
6. Therefore, C2: Some or all folk-psychological mental states/properties may not exist.

Hidden assumption: The standards used to judge scientific theories can be applied to common-sense psychology.
Inference type: abductive, using explanatory comparison and historical analogy.
Main pressure point: P3, because defenders of folk psychology can insist that its everyday success is real evidence in its favour.

Patricia Churchland strengthens the surrounding outlook by rejecting the idea that philosophy of mind can be insulated from neuroscience. Brain-wise presents old problems about self, consciousness and choice as problems to be re-examined within the brain sciences. This supports eliminativism indirectly: if neuroscience can reshape the categories used to understand mind, then common-sense categories should not be treated as untouchable.

The most important distinction is between correction and elimination:

Eliminativism predicts a more radical transformation than reduction. It says that a mature neuroscience may not discover beliefs and desires under different names. It may instead describe cognition using categories that do not preserve the folk-psychological picture.

This makes eliminative materialism initially plausible for three reasons:

1. It is scientifically modest in one sense: it does not demand that future neuroscience vindicate our current mental categories.
2. It explains why introspection and common sense might feel compelling even if they are not theoretically accurate.
3. It fits historical cases where familiar explanatory schemes were abandoned once better theories emerged.

But it also inherits a serious burden. The more radical the claim, the stronger the evidence required. Saying that folk psychology is imperfect is easy. Saying that its central posits do not exist is much harder.

Certainty About Mental States

The first issue is that our certainty about the existence of our mental states may take priority over other considerations. This is the most immediate objection because eliminativism seems to deny what is most obvious.

If I am in pain, it seems absurd to say that pain does not exist. If I am wondering whether eliminativism is true, it seems obvious that I have a thought. If I am anxious, I may be wrong about the cause of the anxiety, but how could I be wrong that some experience is occurring?

The objection can be reconstructed like this:

1. P1: We are directly and securely aware of at least some of our own mental states.
2. P2: Direct certainty about mental states is stronger evidence than speculative claims about future neuroscience.
3. P3: Eliminative materialism denies that some or all common-sense mental states/properties exist.
4. Therefore, C: Eliminative materialism is less plausible than the claim that mental states exist.

Hidden assumption: Introspective certainty reveals the existence of the mental states as folk psychology describes them.
Inference type: epistemic and conceptual.
Main pressure point: P1 and the hidden assumption, because the eliminativist can distinguish having an experience from correctly theorising it.

This objection is strongest when aimed at conscious experience, such as pain or visual sensation. It is less straightforward when aimed at propositional attitudes, such as belief. A person might be confident that something is going on internally, but it does not follow that the best theory of that internal process uses the folk category belief.

Eliminativist reply:

Patricia Churchland's discussion of self-knowledge is useful here. The fact that a judgement about one's own experience is non-inferential does not show that it is metaphysically special or scientifically unrevisable. We can make immediate discriminations without conscious access to the neural processing that produced them.

Residual problem: this reply is more convincing for theoretical categories than for phenomenal states. It is plausible that the science of memory or decision-making may replace belief-desire explanation. It is harder to convince many people that pain itself does not exist, rather than that our theory of pain is incomplete. A careful eliminativist may therefore restrict the strongest claim to some mental states, especially propositional attitudes, instead of denying every aspect of conscious experience.

Folk Psychology As Best Hypothesis

The second issue is that folk psychology has good predictive and explanatory power, so it may be the best hypothesis. This objection accepts the eliminativist's own standard: if theories should be judged by explanation and prediction, folk psychology seems to do well.