This article was originally published by Knowable Magazine.We’ve all heard of the five tastes our tongues can detect: sweet, sour, bitter, savory-umami, and salty. But the real number is actually six, because we have two separate salt-taste systems. One of them detects the attractive, relatively low levels of salt that make potato chips taste delicious. The other registers high levels of salt—enough to make overly salted food taste offensive.

Once upon a time, presidential impeachment was a rare event. But with four of the five inquiries in U.S. history coming in the past 25 years, people seeking to understand and explain the impeachment inquiry into President Joe Biden, launched Tuesday, have looked to the 2019 impeachment of President Donald Trump as an analogy. Both center on allegations of using elected office for personal gain, and both have been divided sharply along partisan lines.

Ever since Elon Musk’s lackeys began fiddling with the algorithms of X (formerly Twitter), I have noticed a distinct shift in the content that is pushed onto users. My “For you” tab is now a nest of tradwives, shoplifting videos, and that guy who has strong opinions on trouser creases. It is also home to the kind of old-fashioned misogyny that I once thought was on the decline.

This is an edition of The Atlantic Daily, a newsletter that guides you through the biggest stories of the day, helps you discover new ideas, and recommends the best in culture. Sign up for it here.Social-media platforms’ attempts to break into commerce have largely flopped.

Footage and eyewitness accounts have conveyed harrowing scenes from the storm-struck Libyan town of Derna: overflowing morgues and mass burials, rescuers digging through mud with their bare hands to recover bodies, a corpse hanging from a streetlight, the cries of trapped children.

From our perspective down here, on the surface of our planet, the stars are tiny, gleaming specks in an inky-dark universe. Occasionally they appear to twinkle, when the air in our atmosphere bends the incoming light. Through telescopes, they are balls of light, their glow distorted by the lens. And up close, the best star in the universe—our sun—is an orangey sphere of flame.But stars can be so much more than that, as telescopes, especially the very good ones, can reveal.

Do you find yourself constantly closing your eyes and seeing marble? Do thoughts of Caesar and chariot races and a nascent republic punctuate your daily goings?All roads lead to Rome—and apparently so do all male thoughts. Across social media, women have been encouraged to ask the men in their life how often they think about the Roman empire and to record the answer.

This is an edition of the revamped Books Briefing, our editors’ weekly guide to the best in books. Sign up for it here.Uncle Tom’s Cabin, first published to colossal success in 1852, has been in reputational free fall ever since.