I confess I've always been very suspicious of this "sequence of exponential growth modes" "model." It seemed to me that "within a century or so" is not much of a prediction. For example, suppose in 2130, economic growth increased dramatically. Robin would be "right," but most of us would have forgotten (mainly by virtue of being dead).

But I do see that I'd failed to find the buried lead in another paper of Robin's, wherein he writes:

"Without machine intelligence, world product grows at a familiar rate of 4.3% per year, doubling every 16 years, with about 40% of technological progress coming from ordinary computers. With machine intelligence, the (instantaneous) annual growth rate would be 45%, ten times higher, making world product double every 18 months!"

Hanson on economic growth with machine intelligence (caution: contains math ;-))

Since he does give a approximate time frame of the next decade or two, I consider that a much more bold prediction. In fact, I don't think it's unreasonable, if it comes to pass, to call it the greatest prediction in the history of economics.

So he'd have that going for him, which is nice...

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1) Kurzweil did update his graphs to 2009 or so for a presentation, but I cant remember which. It may be the one where he is talking with an Army group.

2) I wondered the same thing about non human primates, but my guess is that Hanson would argue that there was growth but tiny. I'd say zero growth and then very tiny but...

3) Intel has argued that computer speed should continue to at least 2029 and this has kept me up worrying some nights....

4) Does anyone have a edition to Omni that was put out in summer 1989? Some author scared the crap out of me by arguing chips in brains by 2030. It was convincing at the time. That sounds like Kurzweil, but I didn't see his name in the special Future issue. (a special future Issue seems redundant for Omni.)

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Why not simply plug in the "population" of "human brain equivalents" into the Solow-Swan growth model?

Why economic growth will be spectacular

According to my calculations there, the number of human brain equivalents added by computers will be:

1 million in 2015 (should not be noticeable)

1 billion by 2025 (should definitely be noticeable)

1 trillion by 2033 (should consistently deliver higher growth per year than ever observed before)

1 quadrillion by 2040 (Singularity territory).

If adding 1 quadrillion people per year to the Solow-Swan growth model doesn't generate some incredibly high numbers, there's something wrong with the model. ;-)

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I hope in the future you declare tests before you've already seen the data.

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I geniunely call bullshit on that. This is inductive reasoning at its worst. No, actually, it is inductive reasoning using CRAPPY data at its worst. A Popperian nightmare.

Seriously, this is just one idea less idiotic that the exponential growth graphs that Kurzweil uses (and that have not changed at all for the past 7 years).

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Evolutionary theory suggests that relatively sudden changes may be the result of symbiont acquisition - so: memes, plants and animals - perhaps.

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I'm glad you're testing your theory, but I have to wonder - what data has come in over the past years contradicting your theory?

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1) I wonder to what extent the World Product estimates on which these models are based were really developed independently of the exponential growth functional forms assumed in these models.

2) That said, if either version of the "sequence of exponential growth modes" is accurate, I wonder whether each transition can be associated with some kind of information revolution. E.g. might the animal->hunting WP growth transition primarily be due to the rise of culture (not just DNA, or individual brains) as a means of retaining / transmitting / developing information? And might the other transitions similarly be linked to significant jumps in intelligent beings' information handling/generation/management capacity?

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And, by the way, what is growth among non-human primates?

While in some primate species the males give food and grooming services to females in exchange for sex, you could hardly call that an economy with a GDP that can grow. Not even all human societies have an economy with trade.

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I thought the behavioural modernity idea was based on datings of cave paintings, stone sculptures and ritual burial sites, not on the complexity of stone tools. The one site at which they mention finding those kinds of cultural traces dates from ~19000 ya, which actually seems supportive of the BM idea, if anything.

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Does your model assume a plausible dynamic or is it just statistical extrapolation of time series?

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