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Two ways of seeing colours
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- Prof Jules Davidoff, Goldsmiths, University of London

ABSTRACT: Consideration is given to the tasks that make judgments of colour similarity based on 
perceptual similarity rather than categorical similarity. Irrespective of whether colour categories
are taken to be universal (Berlin & Kay, 1969) or language induced (Davidoff, Davies & Roberson, 
1999), it is widely assumed that colour boundaries, and hence categorical similarity, would be used
in tasks that require colour categorization. However, we found that categorical similarity was more
reliably used in implicit than in explicit categorization. So, in an implicit task (visual search)
judgments were largely based on categorical similarity but perceptual similarity was used in the 
explicit task of matching-to-sample colour. There was a similar strong tendency to ignore colour 
boundaries and to divide the range of coloured stimuli into two equal groups in both Westerners and
in a remote population (Himba).

BRIEF BIO: My academic research as a neuropsychologist began at the MRC, Oxford and at the National
Hospital London where my primary concern was to clarify the relationship between the stored (memory)
knowledge concerning objects and their recognition, categorisation and nameability. The role of 
colour was addressed in my text Cognition through Color published by MIT Press (1991) and has been 
extended in current research. Working in cultures (Papua New Guinea and Namibia) with minimal 
colour lexicons we showed that colour categories derive from the colour terms in a speaker's 
languages. The issue was further addressed with infants and with monkeys in collaborative research 
with the CNRS Marseille