Podcast Summary: ReThinking with Adam Grant

Episode: How to spot psychopaths and narcissists, with Leanne ten Brinke

Release Date: March 10, 2026
Host: Adam Grant
Guest: Dr. Leanne ten Brinke, Social Psychologist, University of British Columbia

Episode Overview

In this episode, Adam Grant sits down with Dr. Leanne ten Brinke to unravel the myths and science behind “dark personalities”—specifically narcissists, psychopaths, Machiavellians, and sadists (collectively, the "Dark Tetrad"). They discuss how to recognize, understand, and manage these personalities both in the workplace and everyday life, covering practical tools for identifying toxic behavior, lesser-known clues, and strategies for self-reflection. The tone is lively yet nuanced, moving beyond pop-psychology labels to evidence-based insight—sprinkled with memorable moments of humor and personal reflection.

Key Discussion Points & Insights

What Are “Poisonous People”? (04:34–07:02)

• Dr. ten Brinke defines "poisonous people": High scorers on the Dark Tetrad—psychopathy, narcissism, Machiavellianism, and sadism.
• Traits breakdown:
  • Psychopathy: Impulsivity, low emotional reactivity.
  • Machiavellianism: Strategic, calculating, manipulative.
  • Narcissism: Grandiosity, entitlement.
  • Sadism: Pleasure from others' pain (newer addition to the literature).
• Spectrum, not binary: "These personality traits...exist on a continuum, right? So like you and I, Adam, we also fall somewhere on each of these traits from low to high." (Leanne, 05:48)
• About 10% of the population display non-clinical but disruptive levels of these traits.

Recognizing Dark Traits: Surprising Clues (Yawns & Smiles) (02:12–04:18; 09:54–12:31)

• Lack of contagious yawn: “People with higher levels of these psychopathic traits are less likely to yawn in return." (Leanne, 02:24)
• Empathy distinction: “...knowing the words but not the music of emotion.” (Leanne, 04:18) – dark personalities can intellectually understand emotions, but not feel them.
• Non-verbal tells: People with dark traits may smile inappropriately when others fail (“schadenfreude”), or display mismatched affect (anger with a big smile).
• Micro-interactions matter: “...people could detect with some level of accuracy how psychopathic this person was based on just watching five seconds of their behavior...” (Leanne, 11:30)

Diagnosing vs. Labeling: Public Perceptions & Outrage (12:31–16:35)

• Social media & ‘toxic’ overuse: Adam and Leanne discuss the risk of over-labeling, noting that enduring small amounts of narcissism doesn’t necessitate cutting people out of your life.
• Reality of harm: Dark traits cause “outsized harm” in organizations and relationships.
• Statistical perspective: Among CEOs, 3% might meet criteria for psychopathy, higher than the general population (1%), but much lower than among incarcerated individuals (20%).
  • “97% of CEOs are not psychopaths. Good news.” (Adam, 16:20)
  • “There’s a ton of reason for optimism and hope about our social interactions.” (Leanne, 16:35)

Dark Traits in Power: Congress, CEOs & Influence (17:27–21:10)

• Research on U.S. Congress: Leanne describes analyzing C-SPAN footage to code non-verbal behaviors linked to dark traits.
  • Findings: Those highest in dark traits were usually less effective at influencing peers and passing legislation. “...they were less able to get other people to work with them.” (Leanne, 19:34)
• Superficial vs. sustainable power: Dark personalities may quickly attract followers or win attention but are poor collaborators long-term.

Dealing with Dark or Toxic People (21:10–27:26)

• When to cut ties: Sometimes distance is necessary, especially in cases of abuse or unchangeable behavior. “Your commitment to them changing does not equal their improvement.” (Leanne, 21:58)
• If you can't avoid them:
  • Build minimal rapport ("tiny common ground").
    • “If you create some sort of little connection with them...people with narcissism were less likely to blow up whenever they got negative feedback.” (Leanne, 23:19)
  • Frame feedback as questions: Reduces perceived dominance threat: "What do you think about changing the reports...?" rather than "We really need to change our reports..." (Leanne, 24:03)
  • Avoid manipulation: Don't try to “beat them at their own game” (lying/manipulating). “You start losing bits of yourself if we try to...beat them at their own game.” (Leanne, 24:58)
  • Set explicit boundaries: “The easiest rules to push on are the ones that you never say and you never make explicit.” (Leanne, 30:12) E.g., “I’m not really interested in talking about that topic. If you come back to that, I’ll have to end this conversation.” (Leanne, 30:56)
• Tailor your strategy: Consider their unique motivations (e.g., attention, money) and find mutual wins when possible.

Self-Reflection: Dark Traits in Ourselves (36:07–38:44)

• We all have a spectrum: “Very few of us score extremely high. But also very few of us score zero on all four.” (Adam, 36:19)
• Adam’s personal reflection: “...the one of these four traits that I occasionally see in myself is a willingness to manipulate others if I think the cause is worthy.” (Adam, 36:44)
• Mitigating darkness in ourselves:
  • Try “agreeableness challenges”—regular small acts of kindness, perspective taking, gratitude—to measurably reduce dark traits.
  • “Over the course of those 16 weeks, people reported being more agreeable and having fewer of those dark personality traits.” (Leanne, 37:58)

Hope & Closing Insights (38:44–39:48)

• Reason for optimism: “It's good news if there are fewer poisonous people in the world than we assume and also if we can actually reduce the number of them.” (Adam, 39:13)
• Early intervention matters: “Every bit of energy and time and dollar that we put into mitigating these traits, especially in youth, returns to us sevenfold by one estimate.” (Leanne, 39:23)
• Final note: Focus on prevention, boundary-setting, and healthy interaction—not on stigmatization or quick labels.

Notable Quotes & Memorable Moments

• On empathy deficits:
  • “People with psychopathy kind of know the words but not the music of emotion.” (Leanne, 04:18)
• On narcissists and self-perception:
  • “If you understand a narcissist or a psychopath, they don’t see anything wrong with saying, ‘I’m better than others or I don’t feel what other people are feeling.’” (Adam, 07:03)
• Quick practical tip:
  • "Frame your feedback in the form of a question...feels less like a shot to their dominance." (Leanne, 24:03)
• On dark leadership:
  • “CEOs are three times more likely to be psychopaths [than the general population]. But also, 97% of CEOs are not psychopaths.” (Adam, 16:20)
• Personal reflection and growth:
  • “The one...trait that I occasionally see in myself is a willingness to manipulate others if I think the cause is worthy...I need to watch out for that tendency in myself.” (Adam, 36:44)

Key Timestamps

• 02:12 Yawning as a measure of psychopathy
• 04:34 Clear definition of “poisonous people” and the Dark Tetrad
• 09:54 Behavioral clues: schadenfreude, inappropriate affect
• 13:27 The dangers of over-labeling ‘toxic people’
• 15:21 Psychopathy among CEOs and inmates
• 18:41 Research: Dark personalities in US Congress
• 21:10 Practical strategies for managing toxic people
• 24:03 Framing feedback and healthy communication tips
• 30:12 Explicit boundary-setting examples
• 36:07 Adam’s self-reflection on his own “dark” tendencies
• 38:44 Hopeful closing: prevalence is lower than we think, and people can change

Tone & Language

• Engaging, objective, and evidence-based—balanced skepticism with actionable empathy.
• Occasional humor, as with Adam's quip: “97% of CEOs are not psychopaths. Good news.”
• Focused on empowerment, both in dealing with others and in self-improvement.

Final Takeaways

• Dark personalities are a small but disproportionately disruptive minority.
• There are behavioral science-backed ways to spot and manage them—especially setting boundaries and reframing communication.
• It’s important not to stigmatize or label too quickly; everyone falls somewhere on the spectrum.
• With awareness and effort, both individuals and organizations can create environments that diminish the impact of toxic traits—leaving more room for kindness, honesty, and productivity.