[mprovost]

"There are only two hard things in Computer Science: cache invalidation and naming things." -- Phil Karlton

https://martinfowler.com/bliki/TwoHardThings.html

[dspillett]

There are only two hard things in Computer Science: cache invalidation, naming things, and off-by-one errors.

[Kavelach]

There are only two hard problems in Computer Science: there's one joke, and it's not even funny

[capableweb]

I prefer the less obvious version of this one:

> There are only three hard things in Computer Science: cache invalidation and naming things.

[giantrobot]

That's the one I use all the time.