17 ms·

Asking it a question most humans wouldn't know the answer to, but which is relatively easy for an AI (volume of a 747, 25th to 34th digit of pi, full name of Ra

Asking it a question most humans wouldn't know the answer to, but which is relatively easy for an AI (volume of a 747, 25th to 34th digit of pi, full name of Ramses the Second) and checking the timing of the result is a pretty good approach for humans looking to detect an AI. Casually switching between English and another language is also pretty surefire if you aren't an English-native speaker and you are talking internationally.

valine 3y ago
I doubt this would work reliably if the LLM system prompt instructs it to play dumb. “Answer this question as a human with 6th grade math skills” is pretty much all that’s needed to defeat your captcha.
- iudqnolq 3y ago
  ChatGPT 3.5 gets the wrong answer but still doesn't sound like a regular human. Saying "we'll need to remember" about something on the right wikipedia page but not actually required to answer the question is a telltale sign of GPT: > To find the 35th digit of pi, we'll need to remember that pi is an irrational number, which means it goes on forever without repeating. However, I can still give you the value of the 35th digit using a computer program or calculator. The 35th digit of pi is 9. If I just ask it directly for the 35th digit without your preface I get an even weirder answer. The 35th digit of PI was definitely known two years ago: > To find the 35th digit of π (pi), we need to count from the first digit after the decimal point. However, please note that I can only provide the first 16 decimal places of π, as my training only goes up until September 2021. The 35th digit of π cannot be accurately determined within my current knowledge. Nevertheless, here are the first 16 decimal places of π: 3.141592653589793
  - valine 3y ago
    I don’t understand how that’s useful as a captcha. How do you evaluate if something sounds human like other than gut feeling?
    - iudqnolq 3y ago
      My gut feeling is that machine learning is pretty good at this kind of text categorization. You could also try going old school and using stylometry. There are a bunch of companies trying to sell GPT detection. But also remember captcha stands for Completely Automated Turing Test to Tell Humans and Computers Apart. Automated isn't necessarily always a hard requirement, for a Turing Test just using your gut is fine.
charcircuit 3y ago
Trivially defeated with a random delay.
- paulpauper 3y ago
  it depends. ask it a hard question and then ask it an equally hard question that incorporates the answer from the first to make it easier, such as computing the n-1 digit after asking it to compute the nth digit. A human will take a long time to answer the nth digit question but then by using the first answer will solve the second one instantly. The AI with delay will take equally long.
  - charcircuit 3y ago
    Just make the second delay shorter. An attacker can quickly implement this while the defender had to spend time thinking of the idea, implementing the new question, and adding the infra for catching bots who answer the 2 differently than humans. Delays are not good proofs of humanity because computers can wait too.

valine 3y ago

I doubt this would work reliably if the LLM system prompt instructs it to play dumb. “Answer this question as a human with 6th grade math skills” is pretty much all that’s needed to defeat your captcha.

iudqnolq 3y ago
ChatGPT 3.5 gets the wrong answer but still doesn't sound like a regular human. Saying "we'll need to remember" about something on the right wikipedia page but not actually required to answer the question is a telltale sign of GPT: > To find the 35th digit of pi, we'll need to remember that pi is an irrational number, which means it goes on forever without repeating. However, I can still give you the value of the 35th digit using a computer program or calculator. The 35th digit of pi is 9. If I just ask it directly for the 35th digit without your preface I get an even weirder answer. The 35th digit of PI was definitely known two years ago: > To find the 35th digit of π (pi), we need to count from the first digit after the decimal point. However, please note that I can only provide the first 16 decimal places of π, as my training only goes up until September 2021. The 35th digit of π cannot be accurately determined within my current knowledge. Nevertheless, here are the first 16 decimal places of π: 3.141592653589793
- valine 3y ago
  I don’t understand how that’s useful as a captcha. How do you evaluate if something sounds human like other than gut feeling?
  - iudqnolq 3y ago
    My gut feeling is that machine learning is pretty good at this kind of text categorization. You could also try going old school and using stylometry. There are a bunch of companies trying to sell GPT detection. But also remember captcha stands for Completely Automated Turing Test to Tell Humans and Computers Apart. Automated isn't necessarily always a hard requirement, for a Turing Test just using your gut is fine.

charcircuit 3y ago

Trivially defeated with a random delay.

paulpauper 3y ago
it depends. ask it a hard question and then ask it an equally hard question that incorporates the answer from the first to make it easier, such as computing the n-1 digit after asking it to compute the nth digit. A human will take a long time to answer the nth digit question but then by using the first answer will solve the second one instantly. The AI with delay will take equally long.
- charcircuit 3y ago
  Just make the second delay shorter. An attacker can quickly implement this while the defender had to spend time thinking of the idea, implementing the new question, and adding the infra for catching bots who answer the 2 differently than humans. Delays are not good proofs of humanity because computers can wait too.