Is it a common view among philosophers that human beings are simply biological computers? Doesn't this view reduce philosophy of mind to solely neuroscience?

It is a common view among philosophers that human beings are biological entities--that, in some sense, our minds (including our conscious mental processes) are our brains (are based on neural processes). There are few substance dualists (who think the mind is a non-physical entity). But in which sense the mind is the brain remains a topic of great controversy (some fancy terms for the relationship between the mental and physical include identity, supervenience, and functionalism).

It should not be controversial that information from neuroscience will inform debates in philosophy of mind. But it is unlikely that neuroscience alone will answer all questions about the nature of mind. Notice that just the way you phrased your question suggests complications. If we did think the brain were a biological computer (this view is one form of functionalism), then many of the details of neuroscience might turn out to be irrelevant. The interesting facts about computers are about their programs (software), but those programs do not depend on the details of the hardware on which they run. That is, computer science is not going to reduce to physics. So, if our minds are like computer programs, then everything about the mind will not be best explained by neuroscience (understood as the study of neural processes).

Conversely, our minds might not be best understood as computer programs that can 'run' on any old hardware. Particular facts about our brains may be crucial to the particular nature of our minds (e.g., consciousness). If so, neuroscience might be crucial for understanding those facts, and consideration of the mind as a computer would not be sufficient to understand the mind.

At a minimum, philosophy of mind will continue to play a crucial role in framing these questions and these theoretical possibilities, and typically philosophers of mind, informed by the relevant scientific information, can help develop new ways of doing the relevant science and can help integrate and interpret the relevant results.

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