# Is parallel processing necessary for AI? **URL:** \ **Category:** Great Debates\ **Created:** [October 18, 2004, 10:01pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912 "2004-10-18T22:01:22Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![Digital\_Stimulus](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Digital\_Stimulus](https://boards.straightdope.com/u/Digital_Stimulus)\ **Post date:** [October 18, 2004, 10:01pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/1 "2004-10-18T22:01:22Z")
In [this](http://boards.straightdope.com/sdmb/showthread.php?p=5382630#post5382630) thread regarding the current state of artificial intelligence, a comparison was made between computers being fast and sequential and brains being slow and parallel. I put forth the argument that, although sequential processing may not be _sufficient_ to attain AI, I don’t think that parallelism is _necessary_. My argument is that some time elapses during the parallel processes that comprise brain function. So long as these processes are performed within that time frame, they will be indistinguishable from those performed in parallel. Is there an established argument for why parallelism must be the case in principle? (Note that I’m not asking about quantum effects, a la Penrose or even the viability of AI a la Searle or Fodor. Just the parallel vs. sequential argument.) ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [October 18, 2004, 10:44pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/2 "2004-10-18T22:44:36Z")
I think I can prove that it is not necessary. If AI is possible on a digital computer of any type, then all algorithms and heuristics used to perform the functions of a mind must be Turing computable. Anything computable using many tapes in parallel is also computable using a single tape. (I believe this was proved in one of my CS courses, I can look it up.) Thus, if any AI program is run in a parallel computing environment, it can also be run in a sequential computing environment, albeit more slowly. If AI is not Turing computable, then everyone is barking up the wrong tree. ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [October 18, 2004, 10:51pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/3 "2004-10-18T22:51:33Z")
> [@Voyager](#): > > If AI is not Turing computable, then everyone is barking up the wrong tree. Assuming the Church-Turing thesis, of course. You do have a point, though: AI may be possible in principle on a sequential machine. That does not mean that it’s practical to pursue that course. What I should’ve said in the other thread is that we don’t know that parallelism is not necessary for usable AI. But all of the intelligence we’ve seen so far has been massively parallel, so there’s reason to believe that it’s the way to go. ---
**Author:** ![Digital\_Stimulus](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Digital\_Stimulus](https://boards.straightdope.com/u/Digital_Stimulus)\ **Post date:** [October 18, 2004, 10:57pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/4 "2004-10-18T22:57:02Z")
D’oh! Of course that’s right. Thank you for filling in my mental lapse; when this comes up again for me (and it will), I’ll be sure to mention you. Next step (and it’s a doozy), someone just has to refute [Fodor’s argument(s)](http://human-nature.com/nibbs/02/harris.html) about mind processes not being Turing computable… ---
**Author:** ![blowero](https://avatars.discourse-cdn.com/v4/letter/b/41988e/32.png) [@blowero](https://boards.straightdope.com/u/blowero)\ **Post date:** [October 19, 2004, 8:40am UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/5 "2004-10-19T08:40:55Z")
Pardon my ignorance, but what is the evidence that the brain reasons in parallel? ---
**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\ **Post date:** [October 19, 2004, 11:06am UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/6 "2004-10-19T11:06:06Z")
What aspect of AI are we discussing here? The ability to have an “experience like us”, or merely the ability to “[have a conversation like us](http://en.wikipedia.org/wiki/Loebner_prize)”? The first is arguably impossible, given the vast and utterly mysterious influence of chemical emotion on responding to sensory input and on “encrypting” memories. The computer might be able to sort its sensory inputs into different levels of memory and find “useful” cross-files associated with it in order to develop some kind of “meaning”, thus acheiving some kind of “consciousness”, but whether this would be anything like what an adult _human_ (or an animal, or even an _insect_) experiences is highly doubtful. As for passing the imitation test, well, each sentence will have to undergo _massive_ processing and analysis in order for each response to be composed. If your test-partner takes more than a few seconds to compose each reply, the game will be up. In this way, I’d suggest that for each word to undergo _serial_ comparison and analysis would require a speed far in advance of what we have now. Parallelism is, in my view, the only way to acheive the _vast_ processing a liguistic sentence requires in order for a convincing response to be composed in a time short enough that it could have come from another human. ---
**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\ **Post date:** [October 19, 2004, 11:11am UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/7 "2004-10-19T11:11:16Z")
**blow** : [The Parallel Brain](http://mitpress.mit.edu/catalog/item/default.asp?tid=8784&ttype=2). I admit I’ve not read this, but I’ve heard it’s quite interesting. ---
**Author:** ![Digital\_Stimulus](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Digital\_Stimulus](https://boards.straightdope.com/u/Digital_Stimulus)\ **Post date:** [October 19, 2004, 1:44pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/8 "2004-10-19T13:44:32Z")
> [@SentientMeat](#): > > What aspect of AI are we discussing here? The ability to have an “experience like us”, or merely the ability to “[have a conversation like us](http://en.wikipedia.org/wiki/Loebner_prize)”? Well, my question was simply directed at the claim that sequential processing isn’t adequate to achieve AI. No particular aspect at all, really. > [@SentientMeat](#): > > The first is arguably impossible, given the vast and utterly mysterious influence of chemical emotion on responding to sensory input and on “encrypting” memories. The computer might be able to sort its sensory inputs into different levels of memory and find “useful” cross-files associated with it in order to develop some kind of “meaning”, thus acheiving some kind of “consciousness”, but whether this would be anything like what an adult **human** (or an animal, or even an **insect** ) experiences is highly doubtful. I assume you’re talking about _qualia_. That, or the “what is it like to be a bat?” question (Nagle). As to the former being impossible, the debate rages on. As to the latter, the more I observe humans, the less I’m convinced the phrase “human experience” has any real (that is, universally applicable) meaning. Obviously, there is a difference between human and insect. It seems to me that, as poor as the explanatory power of _functionalism_ is, it may be the only way to actually make a judgment. > [@SentientMeat](#): > > As for passing the imitation test, well, each sentence will have to undergo **massive** processing and analysis in order for each response to be composed. If your test-partner takes more than a few seconds to compose each reply, the game will be up. > > In this way, I’d suggest that for each word to undergo **serial** comparison and analysis would require a speed far in advance of what we have now. Parallelism is, in my view, the only way to acheive the **vast** processing a liguistic sentence requires in order for a convincing response to be composed in a time short enough that it could have come from another human. First, I believe there’s research that shows that humans parse sentences item by item as words are “exposed”. (This would be eye-tracking, where a subject’s focus of attention is used to gauge what they’re processing.) Much different than the way standard language processing on a computer is done, which creates every conceivable parse tree, assigns “meaning” to each, then chooses appropriately. However, I know there’s research being done to do the parsing in a different fashion. Just not very far along yet. And I’d make the point that there’s no reason _in principle_ that sequential processing couldn’t do the job. Perhaps the fact of the matter is that parallelism will prove to be practically better, but I don’t think it’s necessary (in the philosophic sense). ---
**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\ **Post date:** [October 19, 2004, 1:56pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/9 "2004-10-19T13:56:02Z")
> [@](#): > > And I’d make the point that there’s no reason in principle that sequential processing couldn’t do the job. Agreed, it is only a practical consideration. I suppose I was speaking of [qualia](http://plato.stanford.edu/entries/qualia/) in a roundabout way, and indeed of paradoxes similar to the one you mention. My point was (in agreement with your overall view) that all such paradoxes arbitrarily _remove_ some element vital to explaining the experience/illusion of consciousness and say “_Ha!_ Explain it _now_, clever clogs!”. The chemical moderation I referred to which evolved over billions of years might _always_ be missing from AI, but that should not be used as ammunition to claim that we don’t _understand_ consciousness. (After all, we understand and can explain the _weather_, but I can’t engineer a tornado in the lab!) ---
**Author:** ![Digital\_Stimulus](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Digital\_Stimulus](https://boards.straightdope.com/u/Digital_Stimulus)\ **Post date:** [October 19, 2004, 2:28pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/10 "2004-10-19T14:28:33Z")
> [@SentientMeat](#): > > I suppose I was speaking of [qualia](http://plato.stanford.edu/entries/qualia/) in a roundabout way, and indeed of paradoxes similar to the one you mention. Qualia is such an odd point…I’m torn whenever I consider it. I mean, it’s obvious to me that I experience _something_ that I think can be referred to as qualia. On the other hand, it almost seems like a fabrication that allows anti-AI proponents to say “Ha - how do you explain this?!” Personally, if I had to choose, I think qualia is a red-herring; just a reified description of something that comes along with sentience. But, I have to admit, there is that niggling feeling that there’s something to it… ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [October 19, 2004, 8:34pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/11 "2004-10-19T20:34:37Z")
> [@ultrafilter](#): > > Assuming the Church-Turing thesis, of course. > > You do have a point, though: AI may be possible in principle on a sequential machine. That does not mean that it’s practical to pursue that course. > > What I should’ve said in the other thread is that we don’t know that parallelism is not necessary for usable AI. But all of the intelligence we’ve seen so far has been massively parallel, so there’s reason to believe that it’s the way to go. Sure. Most CPUs, today (well, all except perhaps for cheap microcontrollers) implement some sort of parallelism, and the wave of the future is multi-core CPUs. One with 16 processors has already taped out. It will be far easier to implement an AI making use of this - one processor to do vision, one to do speech processing, one to do speech understanding, one for memory control, one for reasoning, one to do meta-reasoning, etc., etc. But being able to write the code to do this is the hard part. ---
**Author:** ![Digital\_Stimulus](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Digital\_Stimulus](https://boards.straightdope.com/u/Digital_Stimulus)\ **Post date:** [October 19, 2004, 8:43pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/12 "2004-10-19T20:43:44Z")
> [@Voyager](#): > > It will be far easier to implement an AI making use of this - one processor to do vision, one to do speech processing, one to do speech understanding, one for memory control, one for reasoning, one to do meta-reasoning, etc., etc. But being able to write the code to do this is the hard part. This is the approach used for a project I was involved with. Two laptops and a mobile robot base that had it’s own internal computer. Vision processing and speech recognition on one laptop, speech production and some higher level “cognitive” stuff on the other laptop, sensory/actuator functions and some other “cognitive” stuff on the robot itself. All the pieces/parts worked fine alone (simulating input as if from the other parts), but when putting it all together, there were…issues. It’s an ongoing project, I must say. ---
**Author:** ![Digital\_Stimulus](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Digital\_Stimulus](https://boards.straightdope.com/u/Digital_Stimulus)\ **Post date:** [October 19, 2004, 8:53pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/13 "2004-10-19T20:53:07Z")
Oh, yeah. The project I just mentioned doesn’t work at the level of parallelism that **Voyager** was talking about, much less what I was getting at with my original question. I felt the need to acknowledge the distinction. (Gotta love abstraction barriers. Whether or not they’ll ultimately serve to retard progress is another matter…) Not that I’m in any way affiliated with it, but the [GRACE](http://palantir.swarthmore.edu/GRACE/) project might be of interest to those reading this thread. ---
**Author:** ![SentientMeat](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@SentientMeat](https://boards.straightdope.com/u/SentientMeat)\ **Post date:** [October 20, 2004, 9:38am UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/14 "2004-10-20T09:38:59Z")
Like the new username, **jk**. I’m reminded of the atrocious Tom Green vehicle “Freddy Underwent Digital Stimulus”. ---
**Author:** ![Digital\_Stimulus](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Digital\_Stimulus](https://boards.straightdope.com/u/Digital_Stimulus)\ **Post date:** [October 20, 2004, 2:34pm UTC](https://boards.straightdope.com/t/is-parallel-processing-necessary-for-ai/269912/15 "2004-10-20T14:34:27Z")
> [@SentientMeat](#): > > Like the new username, **jk**. I’m reminded of the atrocious Tom Green vehicle “Freddy Underwent Digital Stimulus”. Thank you. **blush** After lurking for about a year after the subscriptions were instituted, I decided a new username was in order to go along with my paid subscription. Furthermore, I’ve decided that, if asked for it’s origination, I’m going to say (possibly TMI, but fits right in with your Tom Green reference): Oh, it’s just something I tossed off while thinking of masturbation.