whoomph of chili-peppers Capsicum spp. you could crush some up, filter it and run it through an HPLC to determine the precise quantity of capsaicin - 8-methyl-N-vanillyl-6-nonenamide- [structure above] and then say a particular chilli is this hot in moles per gram. It's complicated by the fact that there are several derivatives of the base capsaicin called capsaicinoids which vary as to their pungency. But chili-bums [aka ring-burners?] had developed a comparative scale at least 100 years ago which is independent of HPLC technology. In 1912, a pharmacist called Wilbur Scoville extracted the peppery volatiles by steeping a precise weight of pepper in alcohol. This essence is then serially diluted in a sugar water until half of a panel of expert tasters cannot detect it. This allows a Scoville Heat Unit scale from 0 for regular bell peppers to much more the 1,000,000 SHUs for chilis like the Carolina Reaper, Bhut Jolokia or Naga Viper. That's a measurement of similarity that is fairly well reproducible even if a dimensional analysis [SI Units?] of what you are actually measuring is not possible.
Good Mythical Morning, [GMM previously]. If that reminds you of Withnail and Matter, I'm with you. That's all mildly interesting . . . not really funny unless you find boxing or cock-fighting [hmmm haven't covered that yet] amusing. What's more interesting is the variability among people as to their capacity to taste/tolerate hot pepper. We had an experiment in this line on a visit to Dublin's Taj Mahal forty years ago.
Metafilter had an interesting compendium recently about 'snacksandsuch' Nate a young feller with a shockin' nonchalance as he chews down on a Chocolate Bhut Jolokia and records his subjective impressions for science. I'm afraid it just made me think of people who wake up from a paracetamol over-dose feeling alright but already doomed to die. But his actions also have a taste of JBS Haldane ruthlessly experimenting on himself for science. If you read the comments on the metafilter post, you'll see that, for several people, chili-chewing is a young man's business. As you pass 30 your tolerance of them changes: not so much in the appetite but in the processing. There is a suggestion that the intestinal flora loses the ability to digest capsaicin as you get older - that's interesting and should be followed up. If your intestinome loses and gains biochemical capability as you age, that may have profound effects in pharmacology. It's sad that Nate adds a note to his Chocolate Bhut Jolokia jaunt "This is my last video. This is because people keep saying my videos are fake." that's a loss for science. But then again, if science post-graduate students burst into tears and went home when a referee dissed their papers, then there would be a lot less science. Then again then again that would possibly be a good thing because 45% of scientific papers have contributed nothing to science. Here's a suggestion that eating chilis burns fat and reduces weight in the obese, young Nate could follow that up and really help his community.