Our subconscious speaks louder than our conscious mind.
I'm 17 years old, and I'm surrounded by great people who really support me in everything I do. The thing is, I can easily tell you, most of them, are nothing but a bunch of phonies. It wasn't hard for me to figure it out, I just had to evaluate them psychoanalytically. I'm no psychologist, but once you really understand the basics of the subconscious mind and how it works, it's nothing but a downhill battle from there.
Psychoanalysists believe that every psychological problem is rooted to the unconscious mind, and most of the movements we make are directly linked to this part of the brain. So one of the first things we can analyze when we are talking to somebody, is their Body movement.
Body Movement: Anyone can easily be lying to you with words, but something that is never going to lie, is how they move. Every time you are speaking eye-to-eye with somebody, you can tell how are they feeling, are they comfortable? Is he nervous? or anxious? You can tell. Body movement is controlled by electrical nervous impulses, so how you are feeling is the way you are moving. Trust me, people notice on your body language.
For example, if you are speaking with someone and they have crossed arms and legs, it means resistance to your ideas. It's some sort of physical barrier against what you are saying, so subconsciously they want to protect themselves so they activate a shield. But hey, these are subtle signs, it's not always black or white.
Or how many times have you seen people giving a speech or a formal presentation playing with their hands and you go like -Oh man that guy's nervous-. You can tell. It's how they move.
"Man's task is to become conscious of the contents that press upward from the unconscious."