The present letter is a very long one, simply because I had no leisure to make it shorter.
Pascal apologized. When you send a message, you ask the receiver for their attention. We acknowledge this every time we say “thank you for your time”. The catch is that good communication takes the sender time too, and their time is no more valuable than the receiver’s. That makes communicating well a matter of respect, not just efficiency.
When the sender skips that work, the result is what we now call slop. It’s communication that asks for more attention than its sender has made a reasonable effort to justify. The sender is responsible for the burden they impose, not for proving how hard they worked. What counts as justified depends on both the context and value of a message. A difficult mathematical proof might legitimately require hours of attention. An RSVP probably shouldn’t.
Slop should not be confused with efficiency. When the sender cuts effort, this can mean one of two things. Either they are removing work nobody needed (this is efficiency), or they are skipping work that still needs doing, delegating it to the receiver (this is slop).
The burden is also heavier than it looks, for two reasons. First, form signals whether a message was carefully reviewed. A careless one leaves receivers unsure what to trust, forcing them to check it themselves. Second, a message is written once but often read multiple times. Spending ten minutes to save each receiver five minutes will pay for itself by the third.
A good message justifies the attention it asks for, and asks for no more than necessary. When you can’t manage both, do as Pascal did: acknowledge it.