A large flock of Canada Geese (Branta canadensis) is making its yearly autumn migration from the Canadian prairies to California. Viewers on the ground can hear them honking away garrulously as they fly in their famous V-shaped wedge. What do they talk about on their long trips? The geese aim for a new topic every year, though in practice they tend to return to the same small number of basic ideas that have been mulled over by generations of geese before them. This year, they are debating, again, the mysteries of migration, under the Topic of the Year, 'Rethinking Innateness'.

Geese like to vocalize all at the same time, and their mode of discourse tends to be less linear than human conversations. The following record is of necessity a linearized and thematized adaptation of a portion of the proceedings, for the benefit of human readers. At the start of this record (though the choice of any particular thread as the 'start' is an arbitrary imposition of the translator) the flock has crossed the U.S. border heading south to the Missouri River .
 

Background to the Debate

"We all agree that migration is a characteristic of our species, that the ability to set a course and navigate long distances appears to develop in every normal gosling under the most varied and sometimes unfavourable conditions, that it unfolds according to a predictable sequence, and is underdetermined by experience. The most reasonable explanation is to suppose that there is a considerable innate component to this ability, and to try to determine what it is. What is there to disagree with in that?"

"That's the trouble with you innatists, anytime you run up against something you can't explain..."

"...because you have no imagination..."

"...because you don't understand how the brain works..."

" ...anytime you run up against something you can't explain, you just say it's innate."

"We do not."

"You innatists, you probably think that we're born with an innate list of edible foods, and that we can't learn about new foods..."

"...I like felafel..."

"...but hold the hot sauce..."

"...you innatists probably think that's impossible."

"We do not. Nobody does."

"You innatists, you probably think we're born with a list of enemies to avoid..."

"...and a list of ponds to go to, so that if one dried up over the summer we would be totally confused..."

"...as if we were, for example, stupid ducks!"

(Chorus of merry honking.)

"No, we don't. We don't believe any of that. Instead of making up crazy arguments to put in our beaks, why don't you try to answer our real points?"

"Go through all that again? Too tedious..."

"...been there, done that. Look, after all these years of fruitlessly pursuing innate solutions, why not give some room to fresh thinking?"

"Fair enough, innatist views were well represented in the last 40 migrations, after about 400 migrations where the environmentalists had the skies to themselves..."

"It's time to restore some balance..."

"...the pendulum's swung too far..."

"...it's time to think again."

"Missouri River coming up ahead, right turn in six minutes. Pass it on"

"Everybody knows that already..."

"...hard to imagine any other course."
 

Plato's Problem for Geese

"The main argument for innateness has to do with the fact that we all know where to fly and when to stop, even in the absence of relevant experience..."

"...we call this the poverty of the stimulus."

"Forty migrations we've been hearing about the poverty of the stimulus..."

"...when it's really a poverty of your imagination..."

"...since we have recently discovered that goslings can learn."

"Who ever doubted that goslings can learn?"

"So there's no poverty of the stimulus. Our world is full of stimuli..."

"...we have the sun in the day..."

"...and the polarized light of the sky when it's dark..."

"...and the stars at night..."

"...and the magnetic field..."

"...not to mention the rivers and mountains and myriad landmarks."

"That's fine for navigating once you know where to go..."

"...but how do we know that, you connectionists?"

"How do we know that? Well, in addition to all the above, we also have...

"...we have Route School!"

"Rocky Mountains coming up. Turn south through the pass, eh?"

"Anything else would be absurd."
 

Route School

"Route School? You don't learn anything worthwhile in Route School."

"Every gosling goes to Route School. Of course you learn things there."

"You learn how to fly in a V..."

"...nobody ever mentions what routes we're going to follow."

"So what? The anserine V is one of the marvels of creation..."

"...the greatest achievement of any species on earth..."

"But what's that got to do with the route?"

"The route! The route! Even Lower Birds can fly a route..."

"...it's the V that makes us special..."

"...without Route School, we'd fly like a bunch of ducks!"

(Honk! Honk! Honk!)

"You innatists, why are you so obsessed with the route? Why don't you ever work on other problems..."

"...problems that regular geese are interested in..."

"...like, for example, how to fly in a V?"

"We don't work on that because flying in a V is such a trivial problem that even a connectionist machine can be trained to learn it..."

"...which is the definition, if you look it up, of a trivial problem. We use the word 'trivial' in a technical sense, of course..."

"...it just refers to a certain class of problems..."

"...like the ones ducks find challenging!"

(Honk! Honk! Honk!)

"Snake River ahead. What do you say we follow it to Twin Falls?"

"That's a no-brainer if there ever was one."
 

Migration as an Emergent

"Anyway, what about goslings that don't go to Route School?"

"All normal goslings go to Route School."

"But say a gosling was removed from its family and transported to another place?"

"That would be an unethical experiment."

"If performed on geese, of course..."

"...but displacement and other kinds of disorienting experiments have been carried out on Lower Birds..."

"...like Starlings, Garden Warblers, crows, pigeons..."

"...and they all show some degree of innate orientation."

"You innatists, if you understood more about the brain..."

"...the millions and millions of connections..."

"...you would understand how migration could emerge without innate preprogramming."

"What does it emerge from?"

"From flying. You fly a little, and you're just going here and there..."

"..but fly a lot, and you're migrating..."

"...migration is an emergent, like the hexagonal shape of the beehive..."

"...or the empty space in the middle of the wedge..."

"...or the spandrels of San Marco."

"Where's that?"

"It doesn't matter, we don't fly there."

"Never mind all that, how does this explain how we know where to fly?"

"As the brain develops, the neural connections are constantly being readjusted..."

"...inputs connect to outputs..."

"...the weights go up and down..."

"...until, as an effect of increasing complexity, the Hidden Units organize themselves into the functional equivalent of what you would call a representation of the route..."

"...and then, we're off to California!"

"And can you show us how that happens, more or less?"

"Not yet, but we can show you how we can train Hidden Units to solve the XOR (exclusive or) problem."

"You connectionists, why don't you train your Hidden Units to recognize the difference between advancing a scientific hypothesis and honking through your chinstraps?"

"There's the Humboldt River coming into view."

"Of course, why wouldn't it be?"

"Say, you innatists and you connectionists, you're both wrong. You think there's something about route following that has to be explained..."

"...but think again."

"Oh, no..."

"...here comes some philosophy from the dark side of the V."
 

Fallacies of Route Following

"You see, it's a mistake to think that we follow a route because there's a model of the route in our heads."

"Why do we do it, then?"

"We just do..."

"...it's our Form of Life."

"Shouldn't we try to explain our Form of Life?"

"Perhaps, but the notion of route following is not a cognitive one..."

"...it's a normative notion: we only know if a goose is following a route correctly if it agrees with what the rest of the flock does..."

"...there are no private routes."

"But the fact is we always follow the same route."

"We do, but we don't have to..."

"..we can choose not to follow our route."

"But we never do."

"We don't want to..."

"...there would be no point to it."

"It wouldn't be more pointless than this discussion."

"We are different from the Lower Birds in our awareness of what we're doing. If you were to ask a flock of ducks why they are flying in a certain direction..."

"...as if you could have a rational conversation with a duck!..."

(Honk! Honk! Honk!)

"...they would have no idea."

"And we do?"

"There's Lake Tahoe. It feels like we're almost there."

"Good thing, too. I wouldn't want to go much further."
 

Epilogue

"So, what's the Topic for the trip back?"

"I don't know, maybe migration is too hard..."

"...we're too close to it."

"Why don't we tackle something more tractable?"

"What about human language?"

"Is there really enough to talk about there for a whole trip?"

"I don't know, language is a species-level characteristic for them, it develops spontaneously in every normal child under the most varied conditions, it unfolds according to a predictable sequence, and is underdetermined by experience..."

"...a classic case, so it would appear, of rich innate principles..."

"...even the silliest goose could see that."

"Except for doing empirical research to find out what the principles are, I don't think there's anything much to argue about there."

"I think that should be pretty clear even to the humans."

"So do we."

"We might all think so, but we should always be ready to think again."
 

References the geese might enjoy consulting:

Alerstam, Thomas. 1990. Bird Migration. Translation of Fågelflyttning by David A. Christie. Cambridge: Cambridge University Press.

Bates, Elizabeth, and Jeffrey Elman. 1996. Learning Rediscovered. Science 274: 1849-50. [Replies and response in Science 276: 1177-80.]

Berthold, Peter. 1996. Control of Bird Migration. London: Chapman & Hall.

Chomsky, Noam. 1986. Knowledge of Language: Its Nature, Origin, and Use. New York: Praeger.

Elman, Jeffrey L., Elizabeth A. Bates, Mark H. Johnson, Annette Karmiloff-Smith, Domenico Parisi, and Kim Plunkett. 1996. Rethinking Innateness: A Connectionist Perspective on Development. Cambridge, Mass.: MIT Press.

Hanson, Harold C. 1997. The Giant Canada Goose. Revised Edition. Carbondale and Edwardsville, Ill.: Illinois Natural History Survey, Southern Illinois University Press.

Kripke, Saul. 1982. Wittgenstein on Rules and Private Language. Cambridge, Mass.: Harvard University Press.