Here’s a simple heuristic for judging the value of information:

The more ephemeral a piece of information is, the less likely it is to be valuable.

Let’s use the news for our first example. Compare a 24-hour constant stream of short stories (CNN, NBC, FOX, etc.) with a less frequent, longer publication (The Economist, Foreign Affairs, New Yorker).

For any given news topic, which source do you expect more informative coverage from? And if you picked a story at random from both kinds, which story do you think would be more relevant in the next week, month, or year?

Since the less-frequent publications need to more carefully select their stories, they will naturally pick stories that are more important, and as a result of their longer format, they’ll explore those stories more in-depth. At the other end of the spectrum, the story pickers at CNN will throw up whatever recently came across their Twitter feed in a desperate attempt to try to fill every waking moment of the day with something that will scare you into sitting through commercials.

CNN’s constant news stream is highly ephemeral. It appears briefly, then disappears, and because of this ephemerality and frequency, it’s typically low-value information. The New Yorker is lower ephemerality, and as a result, has a higher quality bar and tends to provide more valuable information.

We can apply this heuristic to social media, too. Snapchat is by far the most ephemeral social media network since anything you share disappears in 24 hours or less. And since the content doesn’t last and is so easy to share, almost every single thing someone puts on Snapchat is completely pointless, whether it’s pictures of food, blurry bouncy videos from concerts, or some complaint about sitting in traffic.

If we assume that the point of social media is to stay in touch with your friends and see what they’re up to, Snapchat does a terrible job since it magnifies meaningless parts of our daily existence and inundates us with pointless data about our peers’ lives. Staying up to date on your friends via Snapchat requires almost constant checking, just to end up seeing what that girl you haven’t talked to since freshman year is putting on her salad.

Instagram (ignoring their disappointing addition of Stories) does the opposite. Most people won’t post more than one picture a day if any, and when they do they carefully select that picture. They write a caption, they find the best image, they put thought into it. Because of this thoughtfulness and selection, you can get a high-level view of what your friends are up to via Instagram in a few minutes a day.

Instagram is low ephemerality and high value for a given post. Snapchat is high ephemerality and extremely low value for any given post. If you were to pick a post at random from Instagram or Snapchat, it’s much more likely that the Instagram one would give you a useful glimpse into something going on in a friend’s life. And, because of its low ephemerality and higher thoughtfulness leading to less content, Instagram is a much lower time suck (assuming you try to keep up with the same number of people).

Let’s apply it to books. Books don’t disappear, per se, but they do disappear from popularity. A book being extremely popular for a brief period as a result of the author’s fame or an effective podcast circuit is not rare, but books remaining popular for 5, 10, 50 years is extremely rare.

Books that I read because they were popular at that moment have frequently been not great. Books I’ve read that have been popular for decades are almost without exception fantastic. It’s the Lindy Effect: the more recent something is popular, the more ephemeral that popularity is, and the less sure you can be about its actual value.

It applies to articles, too. Anything from BuzzFeed is 100% ephemeral uselessness, anything from Paul Graham is going to be worth reading. This gives us a simple rule for blogs: the more often a blog publishes, the less likely any individual article is going to be good. Sites that are constantly posting are creating artificial complexity and subjecting you to infomania.

We can take any source of information and put it on a chart like this one:

I have yet to think of a good example for the upper left or lower right quadrants. If it’s high value it will tend to last, and if it’s low value it will tend to become ephemeral as a result.

You may be thinking, though, “What’s the point? Why does this matter?” Any time you open Snapchat, turn on the news, pick a book off the bestseller list, you’re making a choice about how you spend your time. There’s an opportunity cost in everything else you don’t spend time on, everywhere else you don’t get information. By picking a highly ephemeral information source, you’re deciding (likely unintentionally) to get lower quality information and to waste your time. By picking non-ephemeral information sources, you get better information in less time.

Recognizing this helps us filter through everything coming at us. You can ask yourself “Is this a highly ephemeral source?” before taking in any piece of new information. If the answer is yes, then you can safely ignore it without any loss.

I guarantee you that if you never check television news, BuzzFeed, or Snapchat, you will miss nothing important.