Private Thoughts: There is No Evidence that I was Born on a Saturday

Abstract

The confident way “There is no evidence” is used in scientific and political circles to silence debate in matters big and small has been a source of constant amazement to me for decades. The first time I heard the phrase was when I was undergraduate at Westminster
Hospital School of Medicine in the mid 1950‟s. I was impressed by the epidemiological articles of Professor Richard Doll linking cigarette smoking to lung cancer. Later, my admiration knew no bounds when article after article continued to pour out of Oxford
University from the pen of Sir Richard Doll, Professor Martin Vessey, and others claiming not only that smoking predisposed to cancer, but also that stopping smoking reduced the chances of cancer. However, debate in the media always managed to find one expert or
other who claimed “there is no evidence that smoking causes cancer”. So loudly, vehemently, and persistently was “there is no evidence” trumpeted that I (and most listeners) began subliminally to interpret “there is no evidence ...” as “there is evidence that smoking does not cause cancer”. Heavy smokers preferred that interpretation too. Next, the phrase assumed a quasischolarly 
connotation, so much so that speakers at any scientific conference that sprinkled their presentations with a few “there is no evidence” statements were considered quite brilliant. They really had done fantastic research to arrive at that conclusion.