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I've never taken one. Question: if you're fundamentally convinced that polygraphs are hokum (as I am), do you actually need any tactics to "beat" them? Or can you just ignore them and handle the interview the same as you'd handle any other interview, and just sort of smile and shrug when the "operator" tells you the machine spat out some significant result? ("Huh, maybe I just had to burp.")


>do you actually need any tactics to "beat" them?

Maybe. Tactics aimed at fooling the machine are really only to bolster the confidence of the person being tested. It's not the case that you're playing against a machine though, the machine doesn't "do" anything; it's a game that you're playing against the examiner.


Right. But polygraphs really are hokum. If you don't doubt that fact, what advantage does the examiner have? Is it that I'd have to account for the fact that they might irrationally believe in the machine, and adjust my performance to fit that irrational belief?

I think what I'm getting at is that the notion of "cheating" or "beating" a polygraph seems like it dignifies the procedure. It's a little like "beating" a psychic medium, isn't it?


What makes you think that the polygraph examiners "believe" in the machine. I'm pretty sure most of them don't. I wouldn't always assume good faith on the part of the examiner, either. In the common use case of culling the herd of police job applicants, polygraph examiners are there to provide a way to arbitrarily reject certain applicants. So, in that case, the applicant basically has to make the examiner "like" him.

It's better than "beating" a psychic medium because there is often a real, valuable prize to be gained (ie: a job).

As far as I am concerned, even submitting to examination dignifies the procedure too much.


If the polygraph examiner doesn't believe in the machine and the candidate doesn't believe in the machine, I'm a little lost as to how the examiner has any advantage, or why you would need any special techniques to "beat" the process.

To be clear: I don't think you do need those tactics, but I'm asking, not asserting; I've never taken a polygraph.


The presence of the machine changes the nature of the interview. It's like how being interviewed on the phone at home and being interviewed handcuffed to a table with a gun your head are different. It really doesn't matter much if the interviewer actually intends to shoot you or not. The mere presence of the prop induces stress making it difficult to think clearly and avoid being manipulated by the interviewer.

To succeed in the situation your mind must be prepared to deal with the gun or the handcuffs or the polygraph. I doubt many people are able to simply ignore them.


The advantage is in them hoping you don't know that machine doesn't work.

In fact they try to check for it. Like they might say things like "it looks like you pizza-ed on this one when you should-a frenchfried, ... hmm that's interesting'. Where say "pizza" and "frenchfry" are polygraph specific terminilogy. If you don't ask "hey what does that mean?" they might assume your read up on and research about how to beat polygraphs.

And on your point of "what if I really don't believe in polygraphs". The problem is the polygraph measures involuntary emotional response. You might rationally not believe in efficacy of polygraphs. But emotionally you'd start breathing faster anyway. Maybe because you are afried the polygraph examiner will figure out that you really know how polygraphs work.


So if that's the only advantage, I can ignore all sphincter-related advice, and the polygraph itself as well. I'm happy about that outcome, by the way!


Based on other comments in the thread and other things I've read, it seems like the polygraph machine serves only to intimidate the interviewee into wearing their emotions on their sleeve, and the real purpose of the polygrapher is to try to read body language.

It also sounds like polygraphers may think they are reading someone, but in actuality just injecting their own bias. I have also never taken a polygraph, but maybe the process to beat is the bias of the interviewer, not the machine.


Right! So isn't it weird to see us proposing things like new tricks to beat the machine? What machine? Can't I just imagine it's a Magic 8 Ball instead? Would we propose tricks to beat a Magic 8 Ball? No!


> What machine? Can't I just imagine it's a Magic 8 Ball instead?

I mean, measuring perspiration, pulse, breathing, and movement is perhaps a step above a Magic 8 Ball. I too am entirely doubtful that anyone can reliably detect deceit with those measurements, but it's hard to have a nonchalant attitude of "this is just a silly game" when you're connected to devices that do in fact actually measure those things.


> I'm pretty sure most of them don't.

Curious.. Why so sure?


> Is it that I'd have to account for the fact that they might irrationally believe in the machine, and adjust my performance to fit that irrational belief?

Well, yeah, wouldn't you? I mean, the fact that you're being given a polygraph implies that your interrogator believes it has some effect that benefits them. And if you're completely convinced that that isn't true, meaning the human-with-polygraph is not more reliable than an unaided human, that still leaves the possibility that the human-with-polygraph is worse in a way that affects you.

If there's a possibility for the device to convince your interrogator that you're being deceptive, but you're honest, you're taking a risk unless you attempt to avoid causing a false positive. Conversely, if there's a possibility for the device to convince your interrogator that you're being truthful, and you're deceitful, you're missing out on an advantage unless you attempt to cause a false negative.

There's no case where your interrogator is better off, so your premise isn't invalidated; the polygraph itself is still bunk. But it's your interrogator's trust in it which has created a relative advantage for you if you play along.

The exact same applies if they show up with a "psychic", although it might be harder -- or easier -- to manipulate.


For me it would be a matter of personal strategy. Basically, is standing on principle the most strategic thing I can do given my goals in the situation that left me on the receiving end of a polygraph?

Even if my strategic goal is to show that a polygraph is meaningless, being able to pass or fail one at will could be really useful to that end.

The odds seem pretty low that any job or clearance requiring a polygraph would let you get by without one, even if you displayed an extensive knowledge of them and how they're flawed. Personally, if acting on principle, I'd probably just not want to work at a place like that to begin with. Of course, I'm sure there are some highly sought after individuals that could get by with that, and it probably depends on whether or not the organization you're engaging with views the polygraph seriously or as a relic on its way out.

If it were something to do with legal proceedings, I'd have to talk to a lawyer first, and see what was in my best interest.

As far as term semantics go (which I think are important), maybe "manipulating" would be a better word than "beating" or "cheating"

edit: The sibling poster also has a really good point about everyone possibly knowing it's a sham, but using it as a tool to get rid of people they want to get rid of. That might be more likely than all my speculation


Ok so I think we may be talking past each other here. I'm not arguing about the legitimacy of polygraphs. They're hokum.

I'm keying in on things like "being able to pass or fail [a polygraph]". "Able" to "pass" or "fail"? Would you say the same thing about being able to pass or fail a psychic palm reading?

I feel like I'm missing something, which is why I keep asking.


The problem is the operator is trying to unnerve you and embarrass you, specifically to fluster you. They don't just just ask you the questions they're interested in. They ask you about your personal sexual habits and other things designed to trigger an emotional response. It's all just a sham. The more honest of a person you are, the less likely you are to pass the polygraph on your first try. And the only way the polygraph works to catch out liars is to use the shame of the situation to coerce a confession out of the person.

Say they ask you "have you engaged in homosexual behavior, especially under the age of 14?" Most people I know, given the situation, will blush. And blushing is basically all a polygraph can actually measure. So now they start berating you that you lied, and if you continue to insist you didn't lie about that particular question, they say it means you lied about a previous one.

The only way to pass a polygraph is to know what they are like and just get through it. Honest people and liars both just need to stick to their stories, regardless of what the polygraph is saying, because eventually they will just fail you and schedule you for another one. Repeat until you've been through it so many times it doesn't phase you anymore. Then their job is done, their job being, "it wasn't my fault if you turn out to be a spy."


Sure! But there are lots of situations in which a counterparty in a discussion has an off-putting advantage (see: every job interview), and yet we don't generally offer advice to candidates along the lines of "tense and relax your anal sphincter repeatedly" or "visualize your happy place on target questions and your worst nightmare on control questions".

Is where I'm going with this clear? I feel like I'm just confusing everyone with this line of questions.

I'm literally just asking:

If I was given a polygraph tomorrow, knowing what I know now (in fact having conviction about what I know about polygraphs), wouldn't a reasonable strategy be to ignore any polygraph-specific advice, and manage the process the same way I would if there was a Magic 8 Ball adjudicating it?

I know there are differences between the plastic toy and the fortune-telling billiard-ball, but are they meaningful?


A magic 8 ball would be just as effective of a prop in the play that polygraph operators play.




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