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The China brain is the name of a thought experiment used in the field of philosophy of mind. This idea, as well as Blockhead, were created by Ned Block as a criticism of functionalism. It is not to be confused with the Chinese room, which is also a thought experiment in philosophy of mind with similar goals.

Contents 1 Background 2 The thought experiment 2.1 Consciousness 3 Criticisms 3.1 Chauvinism 3.2 Liberalism 4 See also 5 References

Many theories of mental states are physicalist. That is, they describe the mind as the behavior of a physical object like the brain. The most prominent example is the identity theory, which says that the mind is the brain. One criticism is the problem of multiple realisability. The physicalist theory that responds to this is functionalism, which states that a mental state can be whatever functions as a mental state. That is, the mind can be composed of neurons, or it could be composed of wood, as long as it provides mental functionality.

Suppose that the whole nation of China was reordered to simulate the workings of a single brain (that is, to act as a mind according to functionalism). Each Chinese person acts as (say) a neuron, and communicates by special two-way radio in the corresponding way to the other people. The current mental state of China Brain is displayed on satellites that may be seen from anywhere in China. China Brain would then be connected via radio to a body, one that provides the sensory inputs and behavioral outputs of China Brain.

Thus China Brain possesses all the elements of a functional description of mind: sensory inputs, behavioral outputs, and internal mental states causally connected to other mental states. If the nation of China can be made to act in this way, then, according to functionalism, this system would have a mind. Block's goal is to show how unintuitive it is to think that such an arrangement could create a mind capable of thoughts and feelings.

The China brain argues that consciousness is a problem for functionalism. Block's Chinese nation presents a version of what is known as the absent qualia objection to functionalism because it purports to show that it's possible for something to be functionally equiavalent to a human being and yet have no conscious experience. A creature that functions like a human being but doesn't feel anything is known as a "zombie." So the absent qualia objection to functionalism could also be called the "zombie objection."

Some philosophers like Daniel Dennett, have concluded that the China brain does create a mental state. Our intuition that this is impossible is just a bias against non-neuron minds, furthered by the implausibility of the scenario. There is a natural desire for us to locate the mind at a singularity because the mind feels to us like it is just one thing. Functionalist philosophers of mind endorse the idea that something like the China brain can realise a mind, and that neurons are, in principle, not the only material that can create a mental state.

The prima facie rejection of China Brain as a true mind is based on Block's critique that functionalism is too "liberal"; that is, it grants mental status to entities that don't really possess minds.

• systems theory
• Chinese room
• Alan Turing
• dualism

• http://www.st-andrews.ac.uk/~sjp7/LM1003/handout_16.html
• Ravenscroft, Ian. Philosophy of Mind: A Beginner's Guide. Oxford, New York. 2005.