To date I've not been able to find any writing by the popular writer on neuropsychological topics Dr Oliver Sacks on the subject of Daniel Tammet. I invite my readers to let me know about any pieces of writing, or material in other media, by Sacks about Tammet that I am unaware of. Tammet is the type of person that one would naturally expect Sacks to write about - Sacks writes about neurological case studies that are curiosities and interesting, and Tammet could be seen as belonging to that category. Tammet has presented himself to the world as an unusual and extreme case of synaesthesia, and Sacks has written some worthwhile stuff about synaesthesia, despite that fact that Sacks lacks a first-hand insight into the condition as a non-synaesthete. The apparent absence of interest in Tammet as a writing subject on the part of Sacks seems odd.
I've got to wonder why Sacks apparently hasn't written about Tammet. I'm tempted to speculate. Could the fact that Sacks is a quite severe case of developmental prosopagnosia be relevant to this matter? Sacks wrote a full and interesting account of what it is like to have a major dose of face-blindness in his last book The Mind's Eye along with a related severe problem with recognizing buildings and landscapes, and this chapter was I believe based on an article that he wrote for New Yorker magazine. Clearly severe prosopagnosia, a face recognition disability, is not a minor issue. It can be a major spanner-in-the-works of one's social life, if Sacks' description of the disability can be taken as a typical experience of prosopagnosics at the more severe end of the scale. Daniel Tammet has also claimed to have a serious disability in recognizing faces, in his second autobiography published in 2009 Embracing the Wide Sky, and also in a 2009 interview with the US version of the 60 Minutes TV show. In Tammet's first 2006 autobiography Born on a Blue Day he claimed to have a poor sense of direction. It is an interesting exercise to contrast Tammet's books with Sacks' written account of life with prosopagnosia. Sacks recounted in detail many episodes of social embarassment and difficulty resulting from his face recognition problems, while Tammet described in his first autobiography Born on a Blue Day finding an old friend who was waiting for him at an airport; "a familiar face", just the type of scenario which I would imagine might be a social nightmare for Sacks. How did Tammet positively identify his old friend? He didn't explain in the book, nor mention any difficulty in doing so. The reader would no doubt assume that Tammet recognized his friends and school acquaintances by their "familiar faces", but this is in stark logical contradiction with Tammet's claim in his second autobiography to have "great difficulty remembering faces, even those of people I have known for many years". Tammet seems to be a most unusual case of prosopagnosia, with an onset in adulthood, for no apparent reason, in between autobiograpies. The author Joshua Foer and myself have both been able to find a variety of pieces of evidence that throw into doubt Tammet's claims about being face-blind, and I have written about this in a post that I published in early October. I can't help wondering whether Sacks has felt skeptical about Tammet as a supposed case of savantism, synaesthesia, Asperger syndrome and prosopagnosia all in one person, one might expect that the best person to detect a pretend prosopagnosic might be a genuine case, and perhaps it might be particularly galling to behold a person who appears to be pretending to have a disability which one genuinely suffers from? I can only speculate.
Oh, and one more point worth mentioning. Did you notice that Oliver Sacks has claimed to have severe face-blindness, but I recall that he has also claimed that he does not experience synaesthesia somewhere in one of his books. Despite the common misconception, prosopagnosia and synaesthesia do not necessarily go together. I believe there are some people who do have both unusual conditions, but I don't think there is any hard evidence that synaesthetes are any more likely to have face memory issues than non-synaesthetes. Some of the earlier, more speculative and less evidence-based writing about synaesthesia from the modern era of synaesthesia research has included speculation that synaesthesia might be linked with issues such as a poor sense of direction, poor left-right discrimination and prosopagnosia, but I don't know of any research that has supported these claims, which appear to have been based on anecodes. In contrast, Tammet claims to have a laundry list of unusual neurological conditions and disorders, as well as a range of disorders of the mind in his family history. I wouldn't be at all surprised if a reading of the earlier, more speculative literature about synaesthesia, such as Dr Richard Cytowic's popular and influential book The Man Who Tasted Shapes was an influence on Tammet when he wrote his first autobiography.