How to tell whether a person is lying or telling you the truth?

  • Thread starter Dx
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In summary, the conversation discusses different theories and methods for detecting lies, including using eye movements, pupil dilation, and lie detection machines. Some members believe that there are certain signs that can indicate lying, while others argue that these signs can be easily faked. Additionally, the reliability of lie detection machines is debated, with some claiming they are not always accurate. The conversation also touches on the ethical implications of using lie detectors and whether they are admissible in court.
  • #1
Dx
Are their any signs eg., eye movement, pupilary response, etc... And are any of you good at spotting the nots?
Dx
 
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  • #2
There are many theories about this, but there's no real way to tell...
I guess if it looks like they're making something up then maybe, but they might have already made up there response already...
Hard to say.
I study psychology and there's nothing from that field I've heard of.
 
  • #3
Originally posted by Dx
Are their any signs eg., eye movement, pupilary response, etc... And are any of you good at spotting the nots?
Dx


Yes - there are some ways that are helpful sometimes.

But I am NOT going to list them, because they will most likely get BLOWN out of porportion and rearanged to say thing they are NOT.

So, if you want to know if someone is lying - get a lye detection machine.

You can buy them at sharperimage
 
  • #4
there are the obvious ones like voice intonation and eye contact, sweating (if they're really nervous), along with much more subtle ones like pupil dilation and nostril flares. if you know what to look for, it's pretty easy to tell.

and in answer to your second question, i am fairly good at picking up these responces, if i say so myself. it helps a lot if you're wearing sunglasses that hide your eyes so that they can't see you looking across their face.
 
  • #5


Originally posted by PhysicsRocks88
So, if you want to know if someone is lying - get a lye detection machine.

lie detection machines are not the best way. sure, they almost always tell you when someone is lying, the problem is they tell you that they're lying when they're not. if your even the slight bit nervous, the machine will pick it up and misinterpret it.
 
  • #6


Originally posted by PhysicsRocks88
Yes - there are some ways that are helpful sometimes.

But I am NOT going to list them, because they will most likely get BLOWN out of porportion and rearanged to say thing they are NOT.

So, if you want to know if someone is lying - get a lye detection machine.

You can buy them at sharperimage

why would i do that? I can build one! Its basically a resistance and temperature machine hooked up to our skin. I believe our skin is about 50ohms which like wire changes with different temperatures that corresponds to our senses. Interesting huh? A cheap one could be built for $5.00 or less. But you get what you pay for and their are more technical diagrams for design of really nice ones. Seriously now, who has time or how could you get someone hooked up to one if they already know their lying? Go ahead and be open and share some secrets please. I won't pick fun or laugh, promise!
 
  • #7
It is not always acceptable to hook everyone up to a lie detector before starting a conversation with them.

Obvious signs are looking away, touching the face, twitching, and looking down and to the left.
 
  • #8
IMO if he/she really wants to lie to you I can't tell. All other signs can be interpreted if you really know how the other person reacts and if he/she is not used to lie to you.
C'mon people you've never lied to your wife about a late meeting at work when you were at the bar watchig the game (whatever game you prefer...)? Did she catch you?
I have to say that I haven't done this very often and I'm not proud of it... so don't do as I do
 
  • #9
Greetings !

The only rather certain ones I know of are eye movements.
When a person's eyes look down and to the left when he's
about to say/answer something he's accessing his brain's
memory and processing parts. When the eyes go up and to the
right his accessing the parts responsible for imagination.
(At least that's what the experts say and it seemed to work
for me.) I suppose there may be other signs that deal with
the same basis (accessing brain functions). I also suppose
that a person could intentionally avoid making such signs
after some practice, if he knows about it of course. At least
these signs are easier to notice and a person has to know
about them to try and avoid them (unlike the more popular
and coomonly faked sweating, shaking, not looking in the eyes
and so on).

Now here's a Q for you - how do you know that someone on the
Internet lies to you ?

Live long and prosper.
 
  • #10


Originally posted by maximus
lie detection machines are not the best way. sure, they almost always tell you when someone is lying, the problem is they tell you that they're lying when they're not. if your even the slight bit nervous, the machine will pick it up and misinterpret it.

1. Stop spreading misinformation. This statement is absolutely 100% false.


2.I have worked with lie detection machines for over a decade - and built many. Never ever EVER has a properly operating lie detection apparatus EVER produced an incorrect result.
 
  • #11


Originally posted by PhysicsRocks88
1. Stop spreading misinformation. This statement is absolutely 100% false.


2.I have worked with lie detection machines for over a decade - and built many. Never ever EVER has a properly operating lie detection apparatus EVER produced an incorrect result.

Is that why they use them in Court?
 
  • #12


Originally posted by Dave
Is that why they use them in Court?


The court using them is another sign that indeed they are beyond a reasonable doubt, yes.
 
  • #13


Originally posted by PhysicsRocks88
1. Stop spreading misinformation. This statement is absolutely 100% false.


2.I have worked with lie detection machines for over a decade - and built many. Never ever EVER has a properly operating lie detection apparatus EVER produced an incorrect result.

almost every phyciatrist (or do i mean phyciologist?) will tell you that lie detector machines are not the best way to tell if a person is lying.
 
  • #14


Originally posted by maximus
almost every phyciatrist (or do i mean phyciologist?) will tell you that lie detector machines are not the best way to tell if a person is lying.


Claims require evidence. Show us all a survey that provides this (mis)information.

BTW - you won't find one.
 
  • #16
Ok I feel I must share with you the only medically proven way to tell if someone's lying. However this is quite complexed, so pay close attention..


1. Look someone straight in the eye
2. Scream at the top of your voice "you're a LIAR!
3. If they confess, they are lying. If not, claim you actually said "you're on FIRE" and act bewildered that they're not.

Write down these steps carefully.

If that fails, just hypnotize them :wink:
 
  • #17
try torcher
 
  • #18
Originally posted by Zantra
Ok I feel I must share with you the only medically proven way to tell if someone's lying. However this is quite complexed, so pay close attention..


1. Look someone straight in the eye
2. Scream at the top of your voice "you're a LIAR!
3. If they confess, they are lying. If not, claim you actually said "you're on FIRE" and act bewildered that they're not.

Write down these steps carefully.

If that fails, just hypnotize them :wink:

Dx LHFAQ!
:wink:
 
  • #19


Originally posted by maximus
lie detection machines are not the best way. sure, they almost always tell you when someone is lying, the problem is they tell you that they're lying when they're not. if your even the slight bit nervous, the machine will pick it up and misinterpret it.

A good polygraph operator will intersperse ordinary questions in with the pertinent questions. This way he gets a baseline for respiration rate, GSR, pulse, etcetra. Currently, polygraphs are considered between 98 and 65% accurate at detecting lies.
 
  • #20
a skilled liar can pass a polygraph, and someone who is telling the truth can fail it miserably if they're very nervous...ergo, the polygraph is codswallop and that's why it's not admissible in most courts of law. however, there is a whole science devoted to the study of lying. you might be able to research it online if you want to find out about it.
 
  • #21
Originally posted by halfdyke
a skilled liar can pass a polygraph, and someone who is telling the truth can fail it miserably if they're very nervous...ergo, the polygraph is codswallop and that's why it's not admissible in most courts of law. however, there is a whole science devoted to the study of lying. you might be able to research it online if you want to find out about it.
Research would also tell you that the polygraph was invented by the same man who came up sith SOMEONE'S favorite magic-lasso wielding superhero! Yep, Wonder Woman's lasso that makes you tell the truth was the idea of the inventor of the lie detector.
 
  • #22
Originally posted by halfdyke
a skilled liar can pass a polygraph, and someone who is telling the truth can fail it miserably if they're very nervous...ergo, the polygraph is codswallop and that's why it's not admissible in most courts of law. however, there is a whole science devoted to the study of lying. you might be able to research it online if you want to find out about it.

I heard a lot of special forces guys are trained to do just that. They're training involves being able to pass a polygraph test if captured to evade questioning and giving up top secret info.


Kool! Not cool as a POW but cool training, i wish i could try doing that, anyone else?
Dx :wink:
 
  • #23
Originally posted by halfdyke
a skilled liar can pass a polygraph, and someone who is telling the truth can fail it miserably if they're very nervous...ergo, the polygraph is codswallop and that's why it's not admissible in most courts of law. however, there is a whole science devoted to the study of lying. you might be able to research it online if you want to find out about it.

A skilled liar is only a little better at passing a polygraph. A pathological liar will pass it every time. A fear of possible detection is important.

Assuming you have a highly skilled operator, just being nervous won't make you fail, but it may make the test invalid - making a baseline unobtainable.

Training with biofeedback can enable you to beat a polygraph, and keeping a small tack thru your shoe, into the toe area, allows you to covertly jab yourself anytime you get a question (baseline or experimental), spiking your readings, thus keeping the operator from determining a baseline.
 
  • #24
Some biological characteristics of lying are:

1) increase in body temperature
2) increase in sweat secretion
3) increase in pulse
4) pupil dilation

Some behavioral effects of lying are:

1) looking down and to the left
2) covering part of the face with the hand
3) crossing the arms
4) general nervousness and broken speech

***HOWEVER*** Not everyone reacts the same way to the same situation. So there is no DEFINITE way to tell whether or not someone is lying. Some people can train themselves to be a good liar by monitoring their behavior or by using biofeedback. That is why the results of a lie detector test cannot be used as evidence in a court of law.
 
  • #25
I have a relative that seems to lie constantly for no reason. None of us can figure out why he lies. He comes with the stupidest stories. I am not sure he even knows he is lying. I have often wondered how he would do on a polygraph test.
 
  • #26
From the police, on television, the manner of cheating a lie detector is by flexing your 'sphincter' muscle, the contractions in your lower body change several of the measurables without the polygraphist being able to tell why.

The method of conclusive "proving of lies" is found in the computer, as apparenlty when you wish to lie, or as you are telling it, there are micro tremors in your facial expression that occur exceedingly rapidly, and a computer can be programed to look at a high speed film, or video, of your face, and find those tremors.

Apparently, that method is considered, and proven(?) 100%
 
  • #27
I like the way they do it on C.S.I.: never mind the person,
follow the evidence.
 
  • #28
I've always thought of different ways to cheat on a lie detector test and I've concluded that it comes down to the mind frame of the individual, the insane can always pass a lie detector because weather they are telling the objective truth or not they believe they are, you can always try going insane yourself. :-)

Otherwise, what about if you think of it as a movie, where you are supposed to be given the correct answers, and think about what your "character" is supposed to say, what his line is, instead of the actual events that are occurring. I don't know how well that would work out under stress, but many could daydream or imagine themselves answering straight line while a director looks on.
 
  • #29
A very good book on this subject: Body Language
 
  • #30
How to tell whether a person is lying or telling you the truth?

Originally posted by Dx
Are their any signs eg., eye movement, pupilary response, etc... And are any of you good at spotting the nots?
Dx

Well, Dx; it really depends on who you are talking to.

For example, there is a way to tell if Bill Clinton is lying:

His lips will be moving!
 
  • #31
How to tell whether someone is lying or not.

Observe their body movements to tell whether someone is lying or not.

1.hand across the mouth; a quick brush of fingers across the lips
2.restricted movements
3.lip licking
4.nervous cough
5.blushing
6.erratic breathing
7.foot tapping
8.slight fidgeting
9.avoiding eye contact
10.eyes shut
11.flattening tones

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