Tutorial: The community of knowledge hypothesis

What is externalism?

• learning depends upon other people’s knowledge (not merely one’s own)

What is psychological essentialism?

People’s concept of a natural kind of knowledge about a categories most central feature

What is transactive-memory? And what are some examples?

The memory of a group includes information shared between individuals

• couples rely upon each others’ expertise to store and recall memory

• people misattribute others’ responses to trivia questions to themselves

• people recall less information when they know it’s stored on a computer

What is the illusion of explanatory depth?

Individuals overestimate their knowledge of a topic until they are asked to explain it in greater detail

What is community of knowledge?

People fail to distinguish their own knowledge from other people’s knowledge

• merely believing that someone else understands a topic leads us to believe we know more about that same topic

What was Sloman and Rabb’s experiment 1 conditions/procedure?

tested the community of knowledge hypothesis by eliciting ratings of understanding for newly discovered natural phenomena while varying whether a group of scientists understood it

What were the results of Sloman and Rabb’s experiment 1?

• understanding was significantly higher in the CK condition, than in no-CK condition

• Ratings of understanding were generally low but consistently higher when scientists were said to understand the objects of judgement

• Results suggest that the existence of understanding in a community of knowledge creates the impression of understanding in oneself

What were Sloman and Rabb’s experiment 2 conditions?

• added a condition in which the discovering scientists understood the phenomena, but the explanations were classified and inaccessible.

• If access to communal knowledge is necessary, then secret-but-explained and unexplained phenomena should both elicit lower ratings of understanding than phenomena that are explained publicly

What were the results of Sloman and Rabb’s condition 2?

• ratings of understanding for the fictional phenomena were higher when communal knowledge was ostensibly accessible than when it was inaccessible or nonexistent

• Both existence of knowledge and access to knowledge are necessary for the community of knowledge effect

• as long as data exists people are likely to claim that they understand it, still an effect seen

What were Sloman and Rabb’s experiment 3 conditions?

• further test of the task-demand and understandability explanations

  • Told ppts that phenomena were either very hard or very easy to understand in order to manipulate social pressure

• If social-pressure task demands explain the results from experiments 1 and 2 then stating that the phenomena are hard to understand should alleviate some pressure and reduce differences in ratings of understanding between the no-CK condition and CK condition

What were Sloman and Rabb’s experiment 3 results?

Made no difference, as long as there was some community knowledge

What were Sloman and Rabb’s experiment 4 conditions?

reducing the minimal descriptions of the stimuli even further to control for how ppts might've taken the description as an explanation - inflating their understanding

• Changed measure of comprehension from 1-7 to 1-100

• Included more nonsense items so there's a general cluster of things that they're reporting they understand, reduced description so easier to admit

What were Sloman and Rabb’s exp 4 results?

effect is smaller but still significant