From Pete Davies
Brian Clegg asks if the vaunted “experimenter effect” of parapsychology might occur in other fields (27 March, p 30).
In Surely You’re Joking, Mr Feynman! Richard Feynman relates the history of attempts to accurately measure the charge of an electron that demonstrate precisely that effect. He goes on to mention methods critical to the scientific process which help to combat this tendency to find what one is looking for.
It is well known in all branches of engineering that the only way to test properly a new design, software module and so on, is to get a third party to do the work. Designers are known to subconsciously “protect” the fruits of their imagination and labour, whereas someone with less emotional investment can be more objective, and find problems that would otherwise not be considered.
Bristol, UK
