Neurorelativism

The weak version of Neurorealism. It holds that different nervous systems (species, individuals, or even brain states) produce different subjective realities, and none has epistemic privilege. It is a biological relativism: truth is relative to the neuron. Attractive for respecting neurodiversity and animal consciousness, but faces the problem of how to communicate or compare distinct neural realities. It is used in critical neuroscience and consciousness studies to challenge the idea of a single “normal” brain. However, if taken to extremes, it can undermine the possibility of any objective neuroscience.

Example: “Neurorelativism claims that synesthesia (seeing sounds as colors) is not an illusion – it is a different neural reality from yours. But if everything is relative to the brain, how do we explain that two synesthetes agree on which colors each sound has?”

Neurodeterminism

The strong version of Neurorealism. It asserts that our neural structure inexorably determines every perception, thought, emotion, and decision. There is no free will, no plasticity capable of escaping neural pathways fixed by evolution or genetics. It is a radical position that reduces the person to their brain, often associated with strong interpretations of fMRI studies or eliminativist theories. Neurodeterminism is criticized for ignoring neuroplasticity, learning, social contexts, and the fact that the brain itself changes with experience. It also faces the performative contradiction that if all beliefs are neurally determined, then the belief in neurodeterminism is also just a neural event, not a rational conclusion.

Example: “A neurodeterminist said: ‘You didn’t choose to read this – your neurons determined that you would.’ The interlocutor replied: ‘Then your argument is also determined, not rational. Why should I believe it?’ Determinism bites its own tail.”

Neurorelativism by Abzu Land May 27, 2026