by David Kordahl

James Clerk Maxwell, whose theory of electromagnetism occupies the same physics pedestal as Newton’s theory of gravity, was by all accounts a good-humored and generous man, and a fairly confusing lecturer. Here is a story about Maxwell (admitted to be apocryphal in the math notes that recount it) that suggests something of his character:
Maxwell was lecturing and, seeing a student dozing off, awakened him, asking, “Young man, what is electricity?” “I’m terribly sorry, sir,” the student replied, “I knew the answer but I have forgotten it.” Maxwell’s response to the class was, “Gentlemen, you have just witnessed the greatest tragedy in the history of science. The one person who knew what electricity is has forgotten it.”
This anecdote—this joke—is improved for those who know Maxwell as the preeminent early theorist of electricity. After all, if Maxwell didn’t know how to define electricity, what hope was there for his students?
At risk of over-explaining it, this anecdote gestures toward a piece of insider knowledge. You don’t need to know everything to construct a mathematical theory, and mathematical theories can be more robust than the systems they have been constructed to describe. As I’ve written elsewhere, mathematical techniques that are useful in one area of science tend to be useful in in other areas, not as an exception, but as a rule. Read more »

The first part of the original trolley problem goes like this. A runaway trolley is careening towards five people tied to the tracks. There’s a lever in front of you that could divert it onto a second set of tracks. Unfortunately, there is also a person tied to those tracks. You can either do nothing and let five people die or throw the switch and kill one person – but save the five. What do you do?



How should people on the ‘progressive’ side of politics view patriotism? That question continues to vex those who would connect with what they suppose are the feelings of the bulk of the population. The answer will vary a good deal according to which country we are considering – the French left, for instance, has a very different relationship to la patrie to that of the US or the UK. In the case of the former, the side cast as traitors has historically been seen as the right. In the USA, at least in the second half of the 20th century it has been very different: those who protested against the Vietnam war were cast as the anti patriots. And today, we still hear that the left ‘hates our country’. The accusation is a damaging one, and has been wielded with glee by conservatives whenever they have the chance. So there is a tricky task for the left, it seems: to be seen as with and not against the mass of people in their identification with the nation and its history, without abandoning an internationalist perspective that rises above the narrow nationalism of the conservative.
Talking about “The Enlightenment”, when understood as something like “an intellectual and philosophical movement that dominated the world of ideas in Europe during the 17th and 18th centuries” (thanks, 
Sughra Raza. Untitled, April 2021.



car when driving alone. Yet my momentary career as a musical performer—exceedingly brief as it may have been—enjoyed a spotlight rarely offered to others.
