How do we understand the behavior of others?: The agency system

1. How do we understand the behavior of others?:The agency system Clark Barrett UCLA barrett@anthro.ucla.edu

2. Heider and Simmel (1944)

3. What is agency? • Agency = the capacity to act in a goal-directed (intentional) way • Humans use the “intentional stance” (Dennett 1987) to interpret and make predictions about behavior. • Main question: What cognitive mechanisms allow us to do this?

4. Talk outline • Research goal: searching for building blocks of the agency system • Perceptual templates / schemas • Conceptual schemas • Switching the system on and off • Interactions with other systems: agency and social cognition • Concluding speculations

5. Why should you care? (Why is the agency system important for culture, norms, and evolution?) • A) A security guard fails to detect a terrorist  50 people die. • B) A security guard throws a grenade into a plane full of passengers  50 people die. • Perhaps understanding intentions gets you more than just looking at outcomes? (Intentions in behavioral econ: Blount, McCabe)

6. Decomposing the agency system [Ultimate] goal: a computational account

7. A “black box” account(non-computational) “Theory of mind”, “Belief / desire reasoning”, “Intentional stance” INPUTS OUTPUTS ? Behavior predictions Perceptual cues Judgments & Decisions Knowledge What’s in here?

8. Inside the black box(a modular, or computational, account) Conceptual schemas Perceptual templates / schemas INPUTS Predator-prey schema (AD, ID) OUTPUTS Perceptual cues Social Xch schema Etc. Behavior predictions Knowledge Processor (“ToMM”) Judgments & Decisions Human John Scope restrictors / modifiers Dog Susan Lion Jim Taxa Individuals

9. Inside the black box(a modular, or computational, account) Conceptual schemas Perceptual templates / schemas INPUTS Predator-prey schema OUTPUTS Perceptual cues Social Xch schema Etc. Behavior predictions Knowledge Processor (“ToMM”) Judgments & Decisions Human John Scope restrictors Dog Susan Lion Jim Taxa Individuals

10. Perceptual templates • Achieving (many) goals entail certain kinds of motion: e.g., pursuit • If intentions have motion signatures, “templates” can be made: detectors • Does the mind contain such templates for detecting particular kinds of intentional behavior?

11. What basic motion schemas do people possess?

12. An experimental study of intentional motion perceptionTodd, Barrett, Miller, & Blythe

13. An experimental study of intentional motion perceptionTodd, Barrett, Miller, & Blythe • Question: can people reliably use motion to infer the intentions of agents, and categorize them? • Categories: Pursuit, court, lead / follow, guard, fight, play • Generated by German adults in game context, evaluated by second set of judges (free descriptions, forced choice) • Within categories, no two exemplars alike; must rely on abstract qualities to make judgment

14. 6-category study: German adults

15. German 3-5 yr olds

16. But: • Are Germans just communicating a culturally shared schema to other Germans? • Or are these motion schemas universal?

17. Cross-cultural study: Shuar of Ecuador

18. Cross-cultural study: Shuar of Ecuador

19. 4-category cross-cultural study

20. Shuar and German adults

21. Motion perception: summary • There appear to exist motion schemas for particular kinds of intention • The same templates are present across cultures

22. Conceptual schemas

23. Conceptual schemas Perceptual templates / schemas INPUTS Predator-prey schema OUTPUTS Perceptual cues Social Xch schema Etc. Behavior predictions Knowledge Processor (“ToMM”) Judgments & Decisions Human John Scope restrictors Dog Susan Lion Jim Taxa Individuals

24. Conceptual schemas Perceptual templates / schemas INPUTS Predator-prey schema OUTPUTS Perceptual cues Social Xch schema Etc. Behavior predictions Knowledge Processor (“ToMM”) Judgments & Decisions Human John Scope restrictors Dog Susan Lion Jim Taxa Individuals

25. Conceptual schemas • Function: making inferences about particular kinds of intentional interaction. • May be many, e.g. : • Social exchange, • mating, • parent / offspring, • predator / prey, • kin altruism • Fiske: relational models • Is there evidence for them?

26. Predator-prey schema  Pre-contact  Predator Mutual Prey detects prey detection detects predator  ()() Approach Wait / Flee Wait / Hide Hide / Ambush  Pursuit Key AgentsParameters  predator  knowledge relation  prey  action relation death

27. Study of children’s inferences about predator-prey interactionsBarrett, Cosmides, & Tooby • Shuar (N=28) and German (N=38) 3 to 5 year olds • Simulated predator-prey encounter with plastic models (Jaguar / horse; Lion / zebra) • At each stage, children predict what will happen next • Also infer mental states of predator and prey

28. Example question: When the lion sees the zebra, what does the lion want to do ? • Schema-consistent: • Chase zebra • Catch zebra • Bite zebra • Eat zebra • Kill zebra • Inconsistent: • Go away (N=1 german) • Eat grass (N=1 shuar) • Rest DK or no response 3 yrs 4 yrs 5 yrs

29. Q: When the lion catches the zebra, what will happen? • Schema-consistent: • Lion hurts zebra • Lion kills and / or eats zebra • Inconsistent: • German 3yr: "then he wants to go to the hospital" (not clear if lion or zebra • German 3 yr: "lion climbs up to the window and falls down“ • But: Few unrealistic or “fantasy” answers • German + Shuar similar: surprising on cultural view 3 yrs 4 yrs 5 yrs

30. Summary of responses on predator-prey questions 3 yrs 4 yrs 5 yrs

31. Predator-prey schema: Summary • Predator-prey schema is present at an early age across cultures • Leads to realistic inferences about predator and prey behavior • Similar in very different cultures, uncontaminated by cultural inputs like fairy tales and cartoons • Other schemas?

32. Conceptual schemas Perceptual templates / schemas INPUTS Predator-prey schema OUTPUTS Perceptual cues Social Xch schema Etc. Behavior predictions Knowledge Processor (“ToMM”) Judgments & Decisions Human John Scope restrictors Dog Susan Lion Jim Taxa Individuals

33. Development of social exchange schemaBarrett, Keller, Takezawa, Wichary • Examined children’s judgments of violations of bilateral social contracts • And predictions of reactions of different parties to violations • German 1st and 4th graders

34. Children’s judgments of contract violations

35. Predicted reactions of victim of contract violation

36. Predicted reactions of violator

37. Social contract schema: Summary • Even young children can identify contract violations • Ability to predict other’s reactions in social exchange situations may be useful for moderating one’s own behavior • Future research: what other schemas are there? When do they schemas develop? (e.g. mating?)

38. Switching the agency system on and off

39. Agency detection • Some things are agents, and some are not • Agents require vigilance, and figuring out what they are trying to do • Assuming everything is an agent entails costs • Selects for discrimination between agents and non-agents

40. Agency detection activates appropriate inference systems AGENT NON-AGENT Activate agency system Activate other object system (e.g. substance) Different patterns of inference: Inferences licensed: can’t move, will not react if touched, can be subdivided into pieces that retain properties, etc… Inferences licensed: can move, will react if touched, can hurt you… etc

41. What about dead things?

42. Death as the cessation of agencyBarrett and Behne • Hypothesis: • Agency detection system contains a “remapping” routine AGENT  SUBSTANCE ALIVE DEAD COW STEAK Activate agency system Activate substance system Deactivate agency system, activate substance system Different inference patterns

43. Cross-cultural test of cessation of agency hypothesis • 3 to 5 year old German and Shuar children • Sleep vs death: Animals and people • Target questions: • Can it move? • If you touched it, could it move? • Could it hurt you? • If you made a noise, could it know you were there? • Could it be afraid? • Sleep / death is a strong test

44. Patterns of inference for sleep vs death Move? If touched? Hurt you? Detect you? Be afraid? GERMAN SHUAR

45. Mean # correct responses by population and age German Shuar

46. Cessation of agency: summary • Agency inferences can be switched on and off for a particular object • This aspect of agency detection present by age 4 or earlier • Same developmental trajectory across cultures: suggests core feature of agency system

47. Agency and social cognition Is a norm violated if it is violated by mistake?

48. Intentions and social contract violation • Cosmides (1989: social contracts are agreements to exchange benefits • Cheating = accepting benefit without paying cost • But: Suppose you agree to give your friend $1000 if he will give you his car next week. However, his car is stolen. Has he cheated you? Perhaps intentions are an important part of social contracts.

49. Social contract Wason Social contract rule: “If you give me your watch, then I will give you $10” Watch no watch $10 $5 P ~p q ~q About 75% of people pick violation cards

50. Manipulating intent, incentive, ability • Cover story manipulated so that potential violator either had: • Intent to violate, or violated by mistake • Incentive to violate, or no incentive • Ability to violate, or no ability (except at random) • How do the presence or absence of these factors affect subject’s vigilance for cheaters (card turning patterns)?