The British mathematician Francis Galton was also surprised by the potential precision of a “vox populi”, a voice of the people.3 When he visited a livestock exhibition in 1906, competitors in a quiz estimated the weight of one of the show’s oxen. It transpired that the competitors’ average estimate corresponded to the ox’s actual weight of 1,197 pounds.
Condorcet’s conditions – sufficient expertise and independent judgement – are often far from being fulfilled. In real decision-making situations, the information upon which members of a group base their decisions is frequently the same, or at least similar. This alone means that their voices are not independent of one another.