Nassim Nicholas Taleb, the mathematician, author and academic, has spent much of his career studying investor psychology and the nature of risk. And as the author of the highly influential book The Black Swan reminded us this week, we always notice the downs more than the ups.

“Something goes from one to 10, and then goes back to nine, people freak out,” Taleb told Bloomberg. This was just hours after shares in the world’s dominant supplier of chips for artificial intelligence, Nvidia, plunged 17 per cent amid concerns about the emergence of Chinese AI start-up DeepSeek.