So, over at today's IRREGULAR WEBCOMIC, David Morgan-Mar discusses the creation of good puzzles, a hobby which a number of you share. And he gives a bunch of examples of puzzles that he and his friends created.
And a lot of them look fun to me. So I print out a couple, and I figure out Step 1 in them, and then I start looking for the twist/looking for Step 2, and just don't have the mental energy to care enough to do it.
Now, see, in my mind, a major characteristic of "being smart" is "being interested in figuring things out", and another is "being able to look at things in different and creative ways." So this sort of puzzle creation and puzzle solving is EXACTLY what I think "being smart" is all about.
And I can remember being interested in this sort of thing; and I can remember even being, well, OKAY at it -- I've never been GOOD at it. But in this case, I look at the thing, start with the first part, and get bored before I even get to the twist. Sometimes I kind of get a vague sense of what sort of thing the twist might be, but I just can't work up the enthusiasm to follow through.
So, in effect, I'm significantly dumber than I used to be.
This is an effect of my bipolar II depression. I have a lack of desire and lack of ability to maintain mental effort to the level that is required to solve problems.