An interesting idea has surfaced on the freenet-chat list: is it possible to build a program that creates some sort of a puzzle, whose answer the generating computer knows (and can verify), but which can only be answered by a human being, not by a computer? [Additional requirement: it should be easy for the human to answer the puzzle.] My proposal was to randomly create an image, which should be 1) easily recognizable by a human (say the image of a pet), but 2) complex enough so that no known algorithm could "reverse-engineer" this. [You need a randomly-generated image because otherwise one could build a large database of all the possible images and the correct answers.] Background information would also be very useful - see http://www.digitalblasphemy.com/userg/images/969403123.shtml - it's easy for a human being to identify the animal in the picture, but (AFAIK) impossible to write a program to do the same thing. Ideas? Mark --- All inventions or works of authorship original to me, herein and past, are placed irrevocably in the public domain, and may be used or modified for any purpose, without permission, attribution, or notification.
At 12:59 PM 10/11/00 -0400, Marcel Popescu wrote:
Real-To: "Marcel Popescu" <mdpopescu@geocities.com>
An interesting idea has surfaced on the freenet-chat list: is it possible to build a program that creates some sort of a puzzle, whose answer the generating computer knows (and can verify), but which can only be answered by a human being, not by a computer? [Additional requirement: it should be easy for the human to answer the puzzle.]
My proposal was to randomly create an image, which should be 1) easily recognizable by a human (say the image of a pet), but 2) complex enough so that no known algorithm could "reverse-engineer" this. [You need a randomly-generated image because otherwise one could build a large database of all the possible images and the correct answers.] Background information would also be very useful - see http://www.digitalblasphemy.com/userg/images/969403123.shtml - it's easy for a human being to identify the animal in the picture, but (AFAIK) impossible to write a program to do the same thing.
I don't follow the other list you mentioned, so I don't know what the actual problem to solve is - my guess is that this is an anti-bot protection measure, intended to make sure that only human participants can engage in a conversation. If that's the problem - or if it's similar - you'll also need to make the puzzle difficult enough that it's hard to brute-force or solve statistically - let's say you provide the other party with 20 images, 19 cats and 1 dog, and ask them to identify the dog. What keeps a bot from answering the question 20 times? Let's assume the first arms-race countermeasure prevents answering the question more than once by generating puzzles on-the-fly from known cat and dog images - so the bot just picks an answer randomly, and keeps doing that until they hit. Can God create a rock so big he can't lift it? I think you're barking up the wrong tree, thinking about "known algorithms" and such - just like with crypto, the real way in isn't to attack the strong front door, but to just go around it. This sounds like maybe it's essentially a credentialling/ID problem, where you're generating credentials on the fly based on a short-form Turing test. Can you restate the problem so that instead of a Turing test it's a more familiar multi-channel authentication process? (e.g., require new participants to have "introductions" from existing participants, track introductions, and remove the access for accounts found to be bots, or found to have introduced bots .. or similar.) -- Greg Broiles gbroiles@netbox.com
At 12:59 PM -0400 10/11/00, Marcel Popescu wrote:
An interesting idea has surfaced on the freenet-chat list: is it possible to build a program that creates some sort of a puzzle, whose answer the generating computer knows (and can verify), but which can only be answered by a human being, not by a computer? [Additional requirement: it should be easy for the human to answer the puzzle.]
There are not any examples that I know of that are exponentially harder for computers to solve than for humans to solve. There may be examples which polynomially harder for computers to solve (e.g., 1000 800 MHz Pentium IIIs for 3 hours vesus a single human for one second), but this is not interesting from a crypto perspective. --Tim May -- ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, ComSec 3DES: 831-728-0152 | anonymous networks, digital pseudonyms, zero W.A.S.T.E.: Corralitos, CA | knowledge, reputations, information markets, "Cyphernomicon" | black markets, collapse of governments.
-- At 12:59 PM 10/11/2000 -0400, Marcel Popescu wrote:
An interesting idea has surfaced on the freenet-chat list: is it possible to build a program that creates some sort of a puzzle, whose answer the generating computer knows (and can verify), but which can only be answered by a human being, not by a computer? [Additional requirement: it should be easy for the human to answer the puzzle.]
Origami world. Computer generates a random 3D object out of large polygons with fairly sharp angles of contact, subject to various limits on the way in which the object is generated. Displays 2D image of 3D object. Human infers 3D object from 2D image, infers unseen portions of the image from rules by which the 3D image is generated -- for example that the object must make sense mechanically -- that it should be stable resting on a plane. --digsig James A. Donald 6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG FsI/AmqwnRejJ3WVIhX/j+c0WMncAQoIrw1mt1Zt 4wdSf8gtla5o0J0s/JI1xGJQQmUEc8MrdpkaXGURD
At 11:54 AM 10/12/00 -0400, James A.. Donald wrote:
-- At 12:59 PM 10/11/2000 -0400, Marcel Popescu wrote:
An interesting idea has surfaced on the freenet-chat list: is it
possible to
build a program that creates some sort of a puzzle, whose answer the generating computer knows (and can verify), but which can only be answered by a human being, not by a computer? [Additional requirement: it should be easy for the human to answer the puzzle.]
Origami world.
Computer generates a random 3D object out of large polygons with fairly sharp angles of contact, subject to various limits on the way in which the object is generated. Displays 2D image of 3D object.
Human infers 3D object from 2D image, infers unseen portions of the image from rules by which the 3D image is generated -- for example that the object must make sense mechanically -- that it should be stable resting on a plane.
You seem to be supposing that human perceptual algorithms (and the illusions they produce) are somehow unknowable or unreplicable by nonanimal machinery. This is meat chauvinism. Look into David Marr's _Vision_ for starters... or Grossburg's (of BU) stuff.. Now back to your regularly scheduled spam laced with cryptography
-- At 11:36 PM 10/12/2000 -0400, David Honig wrote:
You seem to be supposing that human perceptual algorithms (and the illusions they produce) are somehow unknowable or unreplicable by nonanimal machinery.
This is meat chauvinism.
Claims of computer vision, and computer walking, and computers doing well anything that a spider can do well, are a mixture of hype and fraud. --digsig James A. Donald 6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG 7N6aeuJRFBnYna+aAOMenoR8XGxuEYD+S3obIVsh 4zJ7VgEMhSpp8c7Y3l1tjow+Rtk1ECNzEcq82V1i3
participants (6)
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David Honig
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Greg Broiles
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James A.. Donald
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Marcel Popescu
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Marcel Popescu
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Tim May