It is absolutely amazing what kind of patternmatching ability the human brain develops after a bit. Sometimes I will look at a completely blank account profile and go "this is spam" and then come back two days later and sure enough, they've filled in the spam.

If you've ever been a moderator of anything for any length of time you can pretty much tag trolls the second they show up. "Yeah, that dude isn't going to argue in good faith." "How can you say that they haven't done anything yet!" <drags on smoke> "Kid, this ain't my first rodeo"

This kind of thing is really really hard to explain to people who don't do it. I don't claim to do it all that well, but man have I run into stuff like this

Spotting what's missing is as much of a clue as spotting what's there, but it's harder to learn.

These kinds of things always make me think of the intermittent discussion in Cryptonomicon of noncomputable processes. I think some parts of our deep pattern matching draw on our entire humanity, every interconnection and synapse, in a way that we could never describe or map.