“There are two types of information: permanent and expiring. Permanent information is: “How do people behave when they encounter a risk they hadn’t fathomed?” Expiring information is: “How much profit did Microsoft earn in the second quarter of 2005?” Expiring knowledge catches more attention than it should, for two reasons. One, there’s a lot of it, eager to keep our short attention spans occupied. Two, we chase it down, anxious to squeeze insight out of it before it loses relevance. Permanent information is harder to notice because it’s buried in books rather than blasted in headlines. But its benefit is huge. It’s not just that permanent information never expires, letting you accumulate it. It also compounds over time, leveraging off what you’ve already learned. Expiring information tells you what happened; permanent information tells you why something happened and is likely to happen again. That “why” can translate and interact with stuff you know about other topics, which is where the compounding comes in.”