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ArgumentThe syntax-and-meaning argument
A program handles only forms; understanding is reaching a meaning. No quantity of rules crosses that gap, which does not condemn every artifact.
Supports Not by program alone
Searle · "Minds, Brains, and Programs" · 1980
- A program is defined entirely by syntax, that is, by the shape of its symbols: one runs it correctly by following rules that speak only of the figure and place of signs, never of what they designate. That is exactly what lets one and the same program run on any machine.
- But understanding is not handling signs, it is knowing what one is talking about, reaching the semantics and not the syntax alone: the signs must relate to something other than themselves, which is called . A system that has only form at its disposal has, of itself, no way of reaching meaning, and adding rules changes nothing, since they are still rules about forms.
- It will be objected that a simulation, if perfect, comes to the same thing. But simulating is not reproducing: the simulation of a storm wets no one, that of a digestion feeds no one. There is no reason to make an exception for understanding.
- The brain, however, genuinely does produce thought: it therefore does not merely run a program, it has causal powers of its own, belonging to what it is and not only to what it computes. Nothing forbids an artifact from possessing them one day, but it will have to reproduce them, not simulate them.
Therefore So running a program will never be thinking, without thought being the privilege of the living: what our machines lack is not life, it is the causal powers of the brain, or a body's engagement with a world.
How far does this reasoning convince you?
Simulating and reproducing
- A simulation reproduces the description of a process, not the process: the weather model that forecasts rain contains not one drop of water, and no one is surprised.
- If this is granted for storms and digestion, one must say why thought would be the exception: either because it is nothing but a formal structure, which is precisely the thesis at issue, or by a privilege granted for no reason.
Therefore Taking the simulation for the thing itself already assumes that thought is nothing but form.
How far does this reasoning convince you?
Intelligence without a body
- Grasping a situation is not running through a list of its features: it is seeing at once what, in this context, deserves attention, a sense of relevance. A child knows one does not joke at a funeral without ever having learned the rule.
- That sense of relevance cannot be put into rules, since a rule would be needed to choose the rule, and so on endlessly. It rests on a know-how acquired by a body that deals with the world, that needs, that moves, that fears.
- , drawing on , concludes not that the machine is impossible, but that the disembodied machine is: an artifact engaged in a world would not fall under the objection.
Therefore This route does not answer the , from which it is independent: it reaches the same middle position by another road. What the program lacks is then not necessarily life: it is a body engaged in a world, which nothing forbids us to build.
How far does this reasoning convince you?