Douglas Hofstadter - I Am a Strange Loop

However, as I pointed out before, if you choose to focus on the particle level, then you cannot draw neat boundary lines separating an entity such as a cell or a hog from the rest of the world in which it resides. Notions like “cell” or “hog” aren’t relevant at that far lower level. The laws of particle physics don’t respect such notions as “hog”, “cell”, “gene”, or “genetic code”, or even the notion of “amino acid”. The laws of particle physics involve only particles, and larger macroscopic boundaries drawn for the convenience of thinking beings are no more relevant to them than votingprecinct boundaries are to butterflies. Electrons, photons, neutrinos, and so forth zip across such artificial boundaries without the least compunction.

If you go the particles route, then you are committed to doing so whole hog, which unfortunately means going way beyond the hog. It entails taking into account all the particles in all the members of the hog’s family, all the particles in the barn it lives in, in the mud it wallows in, in the farmer who feeds it, in the atmosphere it breathes, in the raindrops that fall on it, in the cumulo-nimbus clouds from which those drops fall, in the thunderclaps that make the hog’s eardrums reverberate, in the whole of the earth, in the whole of the sun, in the cosmic background radiation pervading the entire universe and stretching back in time to the Big Bang, and on and on. This is far too large a task for finite folks like us, and so we have to settle for a compromise, which is to look at things at a less inclusive, less detailed level, but (fortunately for us) a more insight-providing level, namely the informational level.

At that level, biologists talk about and think about what genes stand for, rather than focusing on their traditional physico-chemical properties. And they implicitly accept the fact that this new, “leaner and meaner” way of talking suggests that genes, thanks to their informational qualities, have their own causal properties — or in other words, that certain extremely abstract large-scale events or states of affairs (for example, the high-level regularity that golden retrievers tend to be very gentle and friendly) can validly be attributed to meanings of molecules.

To people who deal directly in dogs and not in molecular biology, this kind of thing is taken for granted. Dog folks talk all the time about the temperamental and mental propensities of this or that breed, as if all this were somehow completely detached from the physics and chemistry of DNA (not to mention physical levels finer than that of DNA), and as if it resided purely at the abstract level of “character traits of dog breeds”. And the marvelous thing is that dog folks, no less than molecular biologists, can get along perfectly well thinking and talking this way. It actually works! Indeed, if they (or molecular biologists) tried to do it the pure-physics way or the pure-molecular-biology way, they would instantly get bogged down in the infinite detail of unimaginable numbers of interacting micro-entities constituting dogs and their genes (not to mention the rest of the universe).

The upshot of all this is that the most real way of talking about dogs or hogs involves, as Roger Sperry said, high-level entities pushing low-level entities around with impunity. Recall that the intangible, abstract quality of the primality of the integer 641 is what most truly topples hard, solid dominos located in the “prime stretch” of the chainium. This is nothing if not downward causality, and it leads us straight to the conclusion that the most efficient way to think about brains that have symbols — and for most purposes, the truest way — is to think that the microstuff inside them is pushed around by ideas and desires, rather than the reverse.

CHAPTER 13

The Elusive Apple of My “I”

The Patterns that Constitute Experience

BY OUR deepest nature, we humans float in a world of familiar and comfortable but quite impossible-to-define abstract patterns, such as: “fast food” and “clamato juice”, “tackiness” and “wackiness”, “Christmas bonuses” and “customer service departments”, “wild goose chases” and “loose cannons”, “crackpots” and “feet of clay”, “slam dunks” and “bottom lines”, “lip service” and “elbow grease”, “dirty tricks” and “doggie bags”, “solo recitals” and “sleazeballs”, “sour grapes” and “soap operas”, “feedback” and “fair play”, “goals” and “lies”, “dreads” and “dreams”, “she” and “he” — and last but not least, “you” and “I”.

Although I’ve put each of the above items in quotation marks, I am not talking about the written words, nor am I talking about the observable phenomena in the world that these expressions “point to”. I am talking about the concepts in my mind and your mind that these terms designate — or, to revert to an earlier term, about the corresponding symbols in our respective brains.

With my hopefully amusing little list (which I pared down from a much longer one), I am trying to get across the flavor of most adults’ daily mental reality — the bread-and-butter sorts of symbols that are likely to be awakened from dormancy in one’s brain as one goes about one’s routines, talking with friends and colleagues, sitting at a traffic light, listening to radio programs, flipping through magazines in a dentist’s waiting room, and so on. My list is a random walk through an everyday kind of mental space, drawn up in order to give a feel for the phenomena in which we place the most stock and in which we most profoundly believe (sour grapes and wild goose chases being quite real to most of us), as opposed to the forbidding and inaccessible level of quarks and gluons, or the only slightly more accessible level of genes and ribosomes and transfer RNA — levels of “reality” to which we may pay lip service but which very few of us ever think about or talk about.

And yet, for all its supposed reality, my list is pervaded by vague, blurry, unbelievably elusive abstractions. Can you imagine trying to define any of its items precisely ? What on earth is the quality known as “tackiness”? Can you teach it to your kids? And please give me a pattern-recognition algorithm that will infallibly detect sleazeballs!

Reflected Communist Bachelors with Spin 1/2 are All Wet

As a simple illustration of how profoundly wedded our thinking is to the blurry, hazy categories of the macroworld, consider the curious fact that logicians — people who by profession try to write down ironclad, razor-sharp rules of logical inference that apply with impeccable precision to linguistic expressions — seldom if ever resort to the level of particles and fields for their canonical examples of fundamental, eternal truths. Instead, their most frequent examples of “truth” are typically sentences that use totally out-of-focus categories — sentences such as “Snow is white”, “Water is wet”, “Bachelors are unmarried males”, and “Communism either is or is not in for deep trouble in the next few years in China.”

If you think these sentences do express sharp truths, just ponder for a moment… What does “snow” really mean? Is it as sharp a category as “checkmate” or “prime number”? And what does “wet” really mean, exactly ? No blur at all there? What about “unmarried” — not to mention “the next few years” and “in for deep trouble”? Ambiguities galore here! And yet such classic philosophers’ sentences, since they reside at the level where we naturally float, seem to most people far realer and (therefore far more reliably true) than sentences such as “Electrons have spin 1/2” or “The laws of electromagnetism are invariant under a mirror reflection.”