Science

On February 14, 1990, Voyager 1 was about six billion kilometres from the Sun, beyond the orbit of Neptune and leaving the planets behind, when its camera was turned around for one last series of pictures. Carl Sagan had pushed for the shot for years, against engineers who saw no scientific value in it and some risk to a camera pointed so close to the Sun. In the frame that came back, Earth occupies less than a pixel: a point of pale light caught in a scattered sunbeam. Nothing could be measured in the Pale Blue Dot that had not been measured better from closer up. The picture existed to be seen, and then to be shown. …

Anyone who has learned a piece from the page knows the stage where every note is right and nothing is happening. The fingers find the keys in order. The rhythm is counted, the rests observed, the dynamics marked in pencil and obeyed. A teacher listening from the next room would hear no mistake. And the player knows, with an embarrassment hard to name, that the piece has not yet arrived. The sequence is correct. Something else is missing. …

Some questions arrive late at night and in bad shape. This one came out roughly as: if the universe began at all, why did it begin with anything left to happen? It sounds like the kind of thing one says after the second glass, and I was ready to drop it. Then I found that physicists ask a sharper version of it in print, and that the sharper version is still open. …

“It’s in my DNA” has become the all-purpose explanation for anything that repeats across a family or a civilization: a talent, a temperament, a taste for bread and wine, a tendency to slip on the same wet bar of soap three generations running. The phrase borrows the authority of genetics to describe something that is usually just a stable environment, a copied habit, or an unexamined tradition, and the borrowing is not innocent. Calling a pattern genetic quietly removes it from the category of things anyone chose, or could still change. …

As a kid in Colombia I had a free subscription to La Pura Verdad — the Spanish edition of The Plain Truth, founded in 1934 by Herbert W. Armstrong and mailed out of Ambassador College in Pasadena, near Los Angeles. It was, unmistakably, evangelical literature: prophecy, end-times reasoning, a specific reading of scripture aimed at conversion. I was never a Christian. Nothing about the magazine’s theology took. And yet I kept reading it, issue after issue, because some of the articles were very good — well-researched, well-written, curious about the world in a way that had nothing to do with doctrine. …

Luca Pacioli did not invent double-entry bookkeeping — Venetian merchants had been using it for at least a century before his 1494 treatise wrote the method down — but he did name the discipline’s real trick. Every transaction gets entered twice, once as a debit and once as a credit, and if the two columns ever fail to match, an error exists somewhere in the world the ledger describes. The genius of the system is not that it records money. It is that it manufactures a built-in alarm for reality not matching the record. Historians of science have mostly ignored this as a source of method, filing it under commerce rather than epistemology. But run the same trick on nature instead of a merchant’s warehouse, and a surprising amount of the history of discovery turns out to be exactly this: someone auditing a ledger, finding it would not close, and naming whatever was missing so it would. …

The body in front of the doctor is easy to measure. Weight goes on a scale. Height goes on a chart. Divide one by the square of the other and you have a number — a BMI — that gets entered into a database and flagged if it falls outside a range established in the 1830s by a Belgian astronomer named Adolphe Quetelet who was studying the statistical distribution of soldiers, not the metabolic health of individuals. Quetelet called his formula the Indice de Corpulence. He did not intend it as a clinical tool. He was doing population statistics. …

Updated 2026-05-11 — Added Édith Piaf closing reference (v1.1). Here is the fantasy in its most seductive form: you wake up in your twenty-two-year-old body with everything you know now. Every mistake you’ve made, every silence that should have been words, every door you walked through and every door you didn’t — all of it available as hindsight. What would you change? I ran this exercise on my own life. Seriously, not rhetorically. I picked moments — the ones that still have weight, the ones that show up in the three-in-the-morning inventory. And each time I tried to intervene, I discovered the same thing: the moment I wanted to fix was not self-contained. The person I became was introduced by someone I only met because of a party I almost didn’t attend because of an argument that happened because of the decision I now want to undo. The love that shaped me most was downstream of a failure I would have prevented. The work I am proudest of came from a rejection that, at the time, felt definitive. …

The duck test is one of the cleanest heuristics in the epistemological toolkit: if it walks like a duck and quacks like a duck, treat it as a duck. It works because surface signs are usually entangled with underlying causes. Ducks walk the way they do because of their anatomy; they quack because of the shape of their bill. The surface and the substance are not independent. When you correctly read the surface, you have usually correctly identified the substance underneath. …

Watch a photon leave the surface of the sun and arrive at your retina. Eight minutes earlier it was inside a star; now it is inside an eye. Of all the paths it could have taken — and physics, in some literal interpretations, says it did take all of them — the one that resolves into your day was the one that minimized a quantity called action. Light finds the cheap route. …