Jun 30, 2026 · 24 min · 14 segments
Dr. Robert Cialdini, author of Influence - 5 million copies sold, and one of the most important books Warren Buffett says he's ever read - has spent decades studying why people say yes. He reveals…
Robert CialdiniGuestLynn ThomanHostCan you tell us about reciprocity and give us some examples?
One of the things that we've learned about human behavior that exists in all human cultures, there's not a single society that fails to train its members from childhood in this rule, and that is that we are obligated to give back to others who have first given to us.
One study that was done in restaurants showed that if a server puts on the tray with the bill at the end of the meal...
If the waiter puts a mint on the tray for each diner, the server's tip goes up three point three percent because people give back to those who have given to them, even something as small as a mint.
Now, the researchers showed that if the server put two mints on the tray for each diner, tips went up fourteen percent.
What this tells me is something I advise people who say they go into a new situation, maybe a new employment situation, they want to be more influential within this group, and they go into a room.
They should not say to themselves of the people in that room, "Hmm, who can most help me here?" The question they should ask first is, "Whom can I most help here? Whose circumstances can I elevate? Whose outcomes can I enhance?" Because by this rule that's been installed in every one of those people in that room, they will stand ready to help in return in ways that you see especially valuable for what you need.
Can you tell us about reciprocity and give us some examples?
One of the things that we've learned about human behavior that exists in all human cultures, there's not a single society that fails to train its members from childhood in this rule, and that is that we are obligated to give back to others who have first given to us.
One study that was done in restaurants showed that if a server puts on the tray with the bill at the end of the meal...
If the waiter puts a mint on the tray for each diner, the server's tip goes up three point three percent because people give back to those who have given to them, even something as small as a mint.
Now, the researchers showed that if the server put two mints on the tray for each diner, tips went up fourteen percent.
What this tells me is something I advise people who say they go into a new situation, maybe a new employment situation, they want to be more influential within this group, and they go into a room.
They should not say to themselves of the people in that room, "Hmm, who can most help me here?" The question they should ask first is, "Whom can I most help here? Whose circumstances can I elevate? Whose outcomes can I enhance?" Because by this rule that's been installed in every one of those people in that room, they will stand ready to help in return in ways that you see especially valuable for what you need.
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3 of 5
Waiter Vincent's Tip Hack
The server Vincent quietly changed everything overnight
Blood Drive Persuasion Flip
When a big ask actually boosts compliance
No One-Size Persuasion
The ultimate tactic turns expectations upside down
+2 more clips · 4 min 55 sec of audio in all
7 of 23
Inside Influence: Live with Dr. Robert CialdiniBehavioral Science For Brands: Leveraging behavioral science in brand marketing.Inside Influence Part 2: How Cialdini’s Principles of Social Proof, Scarcity, and Authority Shape Consumer BehaviorBehavioral Science For Brands: Leveraging behavioral science in brand marketing.The rest of this transcript — segmented and speaker-labeled, so you land on the exact moment something was said
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