From Randi, J. 1988. “The detection of fraud and fakery.” Cell Mol Life Sci 44:287-288:
I am a conjuror (often mis-called, 'magician') and as such I have a very powerful, albeit narrow, expertise. I know when people are being deceived. It is difficult to describe how I can come to that conclusion, just as it is difficult to describe how to play the violin, but I have been rather successful in pointing out where certain individuals have allowed themselves to be lead astray. I have not always been thanked for these efforts.