Sense of self

• Mirror test

  • performing self-directed actions when looking in mirror = assumed to be indicator of self-knowledge
  • chimpanzees, oranh-utans, gorillas - 1st react as if another ape - subsequently use for self-inspection
  • doesn't necessarily indicate self-recognition
• Mark tests

  • marks placed in faces of chimpanzees
  • frequency of touching marked & unmarked areas in presence & absence of mirror
  • touched more marks & increased with longer mirror exposure
  • suggest self-awareness?
• Mark test - other animals

  • Similar claims for other great apes: bonobos, gorillas
  • Many failures in other species - monkeys, fish, cats, dogs
  • Even in chimpanzees - result is unusually large
  • Not all chimps passed
• Mirror tests humans

  • babies typically pass around 12 - 18 months
  • huge cultural variations - 3 yr = 84% US, 51% Peru, Fiji 0%
• experience with mirrors 


  • in humans & non-humans = seems to be key prerequisite for passing test
  • dolphins = easily pass variant of mark test - only after extensive exposure to mirrors
• Mark test - pigeons

  • pass with specialised training
  • trained to peck at visible dots on body without mirror
  • trained to peck at dots on walls using mirror
  • pigeons then pecked dots on body previously obscured by bib but visible on mirror
• what does mirror test really tell us

  • do children from Fiji or have prosopagnosia lack sense of self
  • tell about ability to recognise own body in mirror? - animals can do without mirror
• why do only some animals recognise their bodies in mirrors?

  • experience, motivation to interact with 'animal in mirror'?
  • probably differ in sense of self
  • mirror tests unlikely to be diagnostic