Cryptic Polygraphs?

[dstokes7]

Cryptics can innately detect and report lies. If in the future, when Roshar actually has modern-style police (not just city watch), would it be possible to have a Lightweaver cop administer a "polygraph" test with the help of their bonded cryptic, without ever needing a machine? If so, would this Cryptic Polygraph test be harder to fool than Earthen polygraph machines? From what I understand, Earthen polygraph machines work by measuring suble changes in the subject's vital signs, and it is possible for a well-trained and disciplined person to fool the machine into thinking a lie is a truth, or for it to falsely identify a trye statement as a lie if the subject is nervous or stressed. Cryptics, however, seem to be able to detect the truthfulness of the statement directly, regardless of the subject's behavior, which would make them far more reliable. Is that true, or am I misunderstanding something?

[Through The Living Grub He/Him]

3 hours ago, dstokes7 said:

Cryptics can innately detect and report lies. If in the future, when Roshar actually has modern-style police (not just city watch), would it be possible to have a Lightweaver cop administer a "polygraph" test with the help of their bonded cryptic, without ever needing a machine? If so, would this Cryptic Polygraph test be harder to fool than Earthen polygraph machines? From what I understand, Earthen polygraph machines work by measuring suble changes in the subject's vital signs, and it is possible for a well-trained and disciplined person to fool the machine into thinking a lie is a truth, or for it to falsely identify a trye statement as a lie if the subject is nervous or stressed. Cryptics, however, seem to be able to detect the truthfulness of the statement directly, regardless of the subject's behavior, which would make them far more reliable. Is that true, or am I misunderstanding something?

Cryptics are not as powerful as you make them out to be (Coppermind page on cryptics):

Spoiler

Cryptics are not able to inherently tell if something is a lie.^[20]

But your idea still has merit. Shallan thinks that Pattern is more skilled at detecting lies, so perhaps they could be trained this way. A fabrial could be more accessible to everyone though, as it doesn't require every city to have at least one Lightweaver.

[Qianweilian He/him]

I was able to find the source for the Coppermind excerpt kindly provided by @Xiahida. (It’s not like it’s right there or anything) If you dont have current access to RoW, here’s the quote, courtesy of Pattern.

Quote

“I do not think he says things that are fully untrue,” Pattern said. “Which makes his lies the best. Mmm. But I cannot tell automatically if something is a lie. I can simply appreciate them better than most, once I realize what they are.”

2 hours ago, Xiahida said:

But your idea still has merit. Shallan thinks that Pattern is more skilled at detecting lies, so perhaps they could be trained this way. A fabrial could be more accessible to everyone though, as it doesn't require every city to have at least one Lightweaver.

This becomes interesting, as not only does Shallan (actually Veil in the text), say Pattern is merely “skilled” detecting lies, he is “better than most humans.” This suggests that they might be able to sometimes detect lies—although this is just a throwaway comment and unreliable narrator strikes again. It’s possible cryptics can detect better than polygraphs and human perception, it’s possible only Pattern can (maybe something to do with Chana or the double bond?), and it’s possible that there is no real difference between cryptic and human perceptive capacity to determine lies from truth.

Quote

Well, in Veil’s experience, he was more expert at noticing subterfuge than many humans. She waved for him to join her under the awning, still happy to be mostly alone.