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"And this stone, it's the reason behind everything that's happened here so far, isn't it? That's what the Servants have been up to all this time."Once upon a time...
"No. The stone, itself, is the cause of nothing. Our desire for it is the reason and the cause."
-- Allen L. Wold, "The Eye in the Stone"
In the beginning, long before goal-oriented cognition, came the dawn of goal-oriented behavior. In the beginning were the biological thermostats. Imagine a one-celled creature - or perhaps a mere blob of chemistry protected by a membrane, before the organized machinery of the modern-day cell existed. The perfect temperature for this blob is 80 degrees Fahrenheit. Let it become too hot, or too cold, and the biological machinery of the blob becomes less efficient; the blob finds it harder to metabolize nutrients, or reproduce... even dies, if the temperature diverges too far. But the blob, as yet, has no thermostat. It floats where it will, and many blobs freeze or burn, but the blob species continues; each blob absorbing nutrients from some great primordial sea, growing, occasionally splitting. The blobs do not know how to swim. They simply sit where they are, occasionally pushed along by Brownian motion, or currents in the primordial sea.
Every now and then there are mutant blobs. The mutation is very, very simple; one single bit of RNA or proto-RNA flipped, one single perturbation of the internal machinery, perhaps with multiple effects as the perturbation works its way through a chain of dependencies, but with every effect of the mutation deriving from that single source. Perhaps, if this story begins before the separate encoding genetic information, back in the days of self-replicating chemicals, the mutation takes the form of a single cosmic ray striking one of the self-replicating molecules that make up the blob's interior, or the blob's membrane. The mutation happened by accident. Nobody decided to flip that RNA base; radiation sleets down from the sky and strikes at random. Most of the time, the RNA bitflip and the consequent perturbation of chemical structure destroys the ability to self-replicate, and the blob dies or becomes sterile. But there are many blobs, and many cosmic rays, and sometimes the perturbation leaves the self-replicating property of the chemical intact, though perhaps changing the functionality in other ways. The vast majority of the time, the functionality is destroyed or diminished, and the blob's line dies out. Very, very rarely, the perturbation makes a better blob.
One day, a mutant blob comes along whose metabolism - "metabolism" being the internal chemical reactions necessary for resource absorption and reproduction - whose metabolism has changed in such a way that the membrane jerks, being pushed out or pulled in each time a certain chemical reaction occurs. Pushing and pulling on the membrane is an unnecessary expenditure of energy, and ordinarily the mutant blob would be outcompeted, but it so happens that the motion is rhythmic, enough to propel the blob in some random direction.
The blob has no navigation system. It gets turned around, by ocean currents, or by Brownian motion; it sometimes spends minutes retracing its own footsteps. Nonetheless, the mutant blob travels farther than its fellows, into regions where the nutrients are less exhausted, where there aren't whole crowds of sessile blobs competing with it. The swimming blob reproduces, and swims, and reproduces, and soon outnumbers the sessile blobs.
Does this blob yet exhibit goal-oriented behavior? Goal-oriented cognition is a long, long, long way down the road; does the blob yet exhibit goal-oriented behavior? No. Not in the matter of swimming, at least; not where the behavior of a single blob is concerned. This single blob will swim towards its fellows, or away from nutrients, as easily as the converse. The blob cannot even be said to have the goal of achieving distance; it sometimes retraces its own tracks. The blob's swimming behavior is an evolutionary advantage, but the blob itself is not goal-oriented - not yet.
Human observers have, at one time or another, attributed goal-oriented behavior and even goal-oriented cognition to the Sun, the winds, and even rocks. A more formal definition would probably require a conditional behavior, an either-or decision predicated on the value of some environmental variable; convergence, across multiple possibilities and different decisions in each, to a single state of the world.
Imagine, in some mathematical Universe, a little adding machine... that Universe's equivalent of a blob. The adding machine lurches along until it reaches a number, which happens to be 62; the adding machine adds 5 to it, yielding 67, and then lurches away. Is this a goal-oriented behavior, with the "goal" being 67? Maybe not; maybe the number was random. Maybe adding 5 is just what this adding machine does, blindly, to everything it runs across. If we then see the adding machine running across 63 and adding 4, and then adding 2 to 65, we would hypothesize that the machine was engaging in goal-oriented behavior, and that the goal was 67. We could predict that when the machine runs across the number 64, up ahead, it will add 3. If the machine is known to possess neurons or the equivalent thereof, we will suspect that the machine is engaging in primitive goal-oriented cognition; that the machine holds, internally, a model of the number 67, and that it is performing internal acts of subtraction so that it knows how much to externally add. If the "adding machine" is extremely complex and evolutionarily advanced, enough to be sentient and social like ourselves, then 67 might have religious significance rather than reproductive or survival utility. But if the machine is too primitive for memetics, like our chemical blob, then we would suspect much more strongly that there was some sort of evolutionary utility to the number 67.
By this standard, is the swimming of the chemical blob a goal-oriented behavior? No; the blob cannot choose when to start swimming or stop swimming, or in what direction to travel. It cannot decide to stop, even to prevent itself from swimming directly into a volcanic vent or into a crowded population of competing blobs. There is no conditional action. There is no convergence, across multiple possibilities and different decisions in each, to a single state of the world.
Although the blob itself has no goal-oriented behavior, it could perhaps be argued that a certain amount of goal-oriented behavior is visible within the blob's genetic information... the "genes", even if the blob lies too close to the beginning of life for DNA as we know it. The blob that swims into a nutrient-rich region prospers; this would hold true regardless of which blob swam there, or why, or which mutation drove it there. The mutation didn't even have to be "swimming"; the mutation could have been a streamlined shape for ocean currents, or a shape more susceptible to Brownian motion. From multiple possible origins, convergence to a single state; the blob that swims outside the crowd shall prosper. There is a "selection pressure" in favor of swimming outside the crowd. That the original blob was born was an accident - it was not a goal-oriented behavior of the genes "deciding" to swim - but that there are now millions of swimmers is not an accident; it is evolution. The original mutant was "a blob whose metabolism happens to pulse the membrane"; its millions of descendants are "swimmers who sometimes reach new territory".
Along comes another mutation, manifested as another quirk of chemistry. When the temperature rises above 83 degrees, the side of the blob contracts, or changes shape. Perhaps if one side of the membrane is hotter than 83 degrees, the blob contracts in a way that directs the motion of swimming away from the heat. Perhaps the effect is not so specific, leading only to a random change of swimming direction when it starts getting hot - this still being better than swimming on straight ahead. This is the ur-thermostat, even as thermostats themselves are ur-goal-behavior. The blob now exhibits goal-oriented behavior; the blob reacts to the environment in a conditional way, with the convergent result of "cooler living space". (Though a random change of direction is on the barest edge of being describable as "goal-oriented". A directional, swimming-away change is a much clearer case.)
In time to come, additional mutations will pile up. The critical temperature of the heat-avoidance reflex will drop from 83 degrees to 81 degrees (recall that we said the optimum temperature was 80). The heat-avoidance reflex will be matched by a cold-avoidance reflex, perhaps with a critical temperature of first 72, then rising to 79. Despite the seeming purposefulness of this slow accumulation of adaptations, despite the convenience and predictive power of saying that "the blob is evolving to stay within the optimum temperature range", the predictions sometimes go wrong, and then it is necessary to fall back on the physical standpoint - to revert from teleology to causality.
Every now and then, it becomes necessary to view the blob as a bundle of pieces, rather than as a coherent whole. "Individual organisms are best viewed as adaptation-executers rather than fitness-maximizers," saith Cosmides and Tooby, and sometimes it becomes necessary to see individual adaptations as they execute. The less evolved the organism, the more necessary the reductionist stance becomes. Consider the adding machine in the mathematical Universe; if the number 67 does have reproductive utility, then the adding machine might have started out as a random crawler that acquired the reflex to add 4 to 63. Its descendants acquired the reflexes to add 5 to 62, to add 7 to 60, to add 3 to 64, to add 2 to 65, to add 1 to 66.
If viewing the adding machine as a fitness-maximizer, we should be extremely surprised when, on running across 61, the machine adds 8. Viewing the adding machine as an adaptation-executer, of course, the scenario makes perfect sense; the adding machine has adaptations for some contingencies, but has not yet acquired the adaptations for others. Similarly, if the environment suddenly changes, so that 68 is now the maximal evolutionary advantage instead of 67, the adding machine will change slowly, piecemeal, as the individual reflexes change, one by one, over evolutionary time. A generalized subtraction mechanism would only need to mutate once, but genes are not permitted to plan ahead.
The teleological viewpoint often fails, where evolution is concerned. To completely eliminate the teleological viewpoint, leaving only causality, one would never be permitted to say that a particular trait was an "evolutionary advantage" for a mathblob; one would be required to describe the entire history, each individual act of addition and the resulting acquisition of resources, every interaction in which an ancestor outcompeted another mathblob with a different genetic makeup. It is a computationally expensive viewpoint - extremely expensive - but it has the advantage of being utterly true. If - returning to our own Universe - some unique mutant superblob accidentally swims directly into a volcanic vent and perishes, it is a historical fact that fits seamlessly into the physicalist standpoint, however tragic it may seem from the evolutionary view.
Our genes are not permitted to plan ahead, because ultimately, all that exists is the history of lives and matings. Unless the present-day utility of some hypothetical adaptation impacted a problem or competition in our ancestral history, it cannot have affected the historical lives of our ancestors, and cannot have affected the final outcome - us.
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