Tell that to a chimpanzee. Then tell that to someone with down&#x27;s syndrome. Then tell that to someone who was malnourished as a child and whose brain just plain doesn&#x27;t work as well as yours. It would <i>astound</i> me to find that there were no inter-person variations that significantly affected ability-to-engineer-exceptionally. I&#x27;m not going to claim that there are people who fundamentally cannot become exceptional engineers, but I <i>will</i> claim that there exist people who start off so disadvantaged that the life circumstances necessary for them to achieve that goal are so unusual as to never occur - pseudo-illegal nootropics, adopted by best family on earth, elementary school teacher is burned-out tenured physicist, etc.