How to Detect a Liar

There is no single gesture, word, or facial twitch that means someone is lying to you. Anyone who tells you otherwise — “if he touches his nose, he’s lying,” “crossed arms mean deception” — is selling you folklore, not behavioral science. Real deception detection, the kind used by professional interrogators and behavior analysts, works on a completely different principle: not what a person is doing, but whether it has just changed.

This guide teaches that principle and builds it out into something you can actually use — in a relationship, a negotiation, a friendship, a hiring decision, anywhere the truth matters and someone has a reason to bend it.

It covers three layers: the physical cluster that shows up in the first few seconds of concealment, the verbal tells that surface in how a story is told, and the conversational techniques that let you test a story without ever sounding like you’re testing it.

Format: PDF
Delivery: Instant access
License: Personal use only

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