Comments on AI Quotes: Minsky says brains are just machines / by Robert Smith

Yet another in my series of comments on quotes about AI that recently appeared in a Forbes article by Rob Toews. Today’s quote is another one from Marvin Minsky:

“The hardest problems we have to face do not come from philosophical questions about whether brains are machines or not. There is not the slightest reason to doubt that brains are anything other than machines with enormous numbers of parts that work in perfect accord with physical laws. As far as anyone can tell, our minds are merely complex processes. The serious problems come from our having had so little experience with machines of such complexity that we are not yet prepared to think effectively about them.”

I was once berated from the podium by Minsky, but it wasn’t about this nonsense. Wish it had been. Dr Minsky took issue with me about a comment I made after a meandering talk he gave at an AI conference, which included a lengthy exposition on how he felt Rosanne Barr (who was a popular star at the time) should be grateful for the abuse she suffered in her youth because it gave her great material for comedy. But I digress.

To say that a brain is a machine is to warp what the word “machine” means. Of course, brains obey the laws of physics. So do rocks, but we don’t call them machines. And we don’t call an avalanche of rocks a machine, either, even though it is a mechanical process with complex behaviours. Here’s what Webster says that the word machine means:


ma·​chine | \ mə-ˈshēn  \

Definition of machine

 (Entry 1 of 2)

1a: a mechanically, electrically, or electronically operated device for performing a task: a machine for cleaning carpets

b: CONVEYANCEVEHICLE especially AUTOMOBILE

c: a coin-operated device: a cigarette machine

d(1): an assemblage (see ASSEMBLAGE sense 1) of parts that transmit forces, motion, and energy one to another in a predetermined manner

(2): an instrument (such as a lever) designed to transmit or modify the application of power, force, or motion


To get to anything that would fit a brain, we’d have to go to definition d). The first part of that definition includes the word “predetermined,” and the case of brains, one would have to ask, “predetermined by who?!?”. In the second part appears the word “designed,” and we’d have to ask the same question there.

So, let’s do away with the “brains are just machines” assumption: it only holds up as a reduction to the absurd.

Are minds complex processes? Absolutely. But it always amazes me that people have so overlooked what we already knew about complexity by 1986, when Minsky published Society of Mind, from which this quote is drawn. One can argue that complexity science had started at least by the time of Poincare at the turn of the 20th century, but the most groundbreaking observations of the field were well-established by the 1970s. The first organization dedicated to their study (The Santa Fe Institute, where I spent a couple of wonderful summers) was founded in 1984.

By then, people knew that there were very simple systems that yielded intractably complex behaviours. They knew that many complicated systems were very likely to have sophisticated emergent behaviours. While Minsky was right, we hadn’t figured out complex systems like the brain in ‘86, we had most firmly established that we would never figure them out, in the sense of the predetermined or designed behaviour of a machine.

Even today, most people haven’t realized that the defining characteristic of life is that it continuously generates behaviours that are complex, emergent, and self-sustaining in a profound way that defies both predetermination and entropy.

One doesn’t have to resort to religion or the supernatural to realize that our brains, and more importantly, our selves, are not just “machines.” One can do that with science, alone.

Read more on this perspective in my book, Rage Inside the Machine.