William Pickles lecture 1989. Seeing sunflowers.

THE clearest memory I have from my first year as a medical student is of a botany practical. We had the task, one sunny Thursday afternoon, of cutting a very thin slice of a sunflower stem, putting it under the microscope and drawing what we saw. In the textbook there was an illustration of what we should expect to see: as I remember, it showed regular, neatly-'packed cells with several smaller structures inside them. After the bloodletting which always accompanied our efforts at razoring a helianthus, we produced passable copies of this illustration, labelled the parts, and sat back satisfied. The lecturer wandered between the long wooden benches, inspecting our efforts in silence, until he reached the only member of our small group who wastill at work a mature student called Philip. 'Well' he said, 'thank goodness one of you draws what he sees'; and he made us all go and look at what Philip had done. The section on Philip's slide was as poor as those made by the rest of us: the cells were of all shapes and sizes, with their walls torn and their contents half-missing. What was different was that Philip's drawing faithfully reproduced this mess. After we had filed past he went back to making it even more accurate. Having nothing better to do, the other students chatted about this for five minutes or so and reached complete agreement that Philip was wasting his time drawing something that looked so unlike a cross-section of a helianthus stem. In an examination he might even not be able to demonstrate that he knew what ought to be there; and in any case the exercise was pointless since when we qualified we were not going to have sunflowers as patients. It was a small event and I did not expect to give it a second thought. To my surprise though, the memory kept coming back to me as though it were important. It was 30 years before I was able to put a meaning to it: the story was an allegory about the way in which we so often practise medicine, seeing only what we expect to see and defending ourselves in the name of common sense. Rarely do we "see the sunflower as it is.