In this chapter, I argue that it is inappropriate at present to pursue research into the genetic basis of ‘intelligence’ and of other behavioural traits in humans. I do not think that such research should be prohibited, nor that we should ignore research findings that emerge from other studies and that give us insight into these areas, but I doubt the wisdom of conducting research designed specifically to identify ‘genes’ or ‘genetic variation’ that contributes substantially to the normal variation in human cognitive abilities and behaviours. Set out below are the various arguments that have brought me to this judgement, probably as much from temperament as deliberation. These considerations can be arranged on a variety of different levels:

1. First are a number of contextual issues such as what is intelligence? Why is it valued so highly? What is it that motivates some scientists to invest so much effort in attempts to measure intelligence, and especially to assess and rank their fellow humans? What lessons can be learned from previous attempts to measure the (intellectual and moral) worth of individuals and races/population groups?

2. Research aimed at identifying genetic variation associated with inter-individual differences in intelligence within the ‘normal range’ is relatively unlikely to yield important and replicable results and may consume much time, effort and resources.

3. Such research is unlikely to identify biological determinants of intelligence in ‘normal’ individuals or any clearly beneficial application in medicine or other social realms.

4. What is true of intelligence will be broadly true also of other personality characteristics, although the demarcation between ‘normal’ and ‘abnormal’ behaviours may be more difficult to define in some of these areas.

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