In our reading group this week, we read John Searle’s classic paper “Minds, Brains, and Programs.” In the paper, he makes the claim that digital computers doing symbol manipulation cannot have intelligence. His motivating example is what he calls the Chinese Room Experiment. Basically, a man is inside a room. He is given a set of instructions to follow when he receives papers full of Chinese symbols. By following the instructions, he creates a second set of symbols which he returns. Although he does not personally understand Chinese, to an observer outside the room, they have just received fluent answers to questions in Chinese. Searle claims that this shows that intelligence cannot be created in a digital computer (the man) with a program (the instructions) because in this example the man clearly does not understand Chinese. I would argue that the room as a whole understands Chinese, as its the whole system that understands it (you wouldn’t expect a computer to be intelligent without its program). He argues that the system as a whole cannot have intelligence, and that some subsystem must have it. But the same systems rule applies to the brain, the brain as a whole has intelligence, but you can’t ascribe the intelligence to any subsystem of the brain such as a neuron or brain region.

The other main thing that bothers me about Searle’s essay is that he claims that human intelligence can never be replicated on a digital computer because a computer does not have the same “causal properties” as the brain. He claims that our intentionality is somehow created by these “causal properties” inherent to the brain that cannot be replicated in a computer. He makes no claim as to what they are or why they can not be replicated. I find it highly unlikely that our intentionality is due to some specific physical feature of the brain as opposed to an emergent property of the coalition of neurons in our brain. It seems like Searle is searching for some little homonculi in our brain that is directing things, and that we can’t recreate that homonculi in a computer. But there is no little man inside our brains.

One interesting point that Searle brings up is the separation of mind and brain. The separation of mind and brain may not be the same as the separation of a program and a computer. While a program can be run on any number of equivalent computers, the mind may be dependent on specific properties of the brain, or may be integrated in the brain rather than being some program that can be applied on top of the brain. I can agree that there are probably some aspects of the brain that are essential to mind, although I don’t see why we won’t be able to simulate those somehow in a computer.