I'm an unappealing nerd now, but in high school I was really an unappealing nerd. I'm talking mostly about physical nerdiness, here. Socially, I was okay. I had an equal number of male and female friends (and these latter were popular and attractive), and I had charm and social guiles enough to make my way in non-nerd society. So I wasn't a D&D playing outcast who could only talk about video games or Star Wars or something.
Okay, the guys and I played D&D one summer in high school. Oh, and were we the object of the girls' vituperation for that.
But anyway. Physically, I was a scrawny, ungainly, goofy anti-jock that, you might reasonably assume, no cute girl would ever notice, much less admire. But oddly, despite all my flaws and through no effort of my own, I received attention from a couple of very good-looking girls. No Lothario's or even an average high schooler's success rate, but pleasantly surprising given what I had to work with. So, why was I somewhat popular with the ladies? Because I was extremely intelligent. Even among a circle of privately-educated, literature-reading, creative and talented people, I stood out as extraordinarily smart.
(No false modesty here, just as no dissimulation in detailing my many failures.)
And intelligence, to women, is an aphrodisiac. Up to a point.
Because, although I'm only slightly more dumbed-down now (when you leave an academic setting, you stop being challenged mentally and so stop growing, no matter how many classics you read or cryptic crossword puzzles you do), my intelligence is now no selling point to women.
What's the difference? I'm glad you asked. Here's my theory. In high school and in college, I was still a potential waiting to be realized. My intelligence implied that I would make something spectacular of myself. So women (and in college this became true on a consistent basis) overlooked my ridiculous exterior and found my intelligence attractive: it was a possible path to power. "Men go for looks, women go for status." Smart men tend to make money, and, let's face it, chicks dig the money. So a young smart man? A good bet for a young woman.
Now, however, as I approach middle age but remain steadfastly rooted in mediocrity if not outright failure, my intelligence is no longer such a starring attraction. Indeed, it's almost like a freakish deformity: since my life is such a disaster despite my intelligence, my very psyche must be defective in some way. I'm like a child prodigy who never got any better at doing math or playing an instrument, and so ends up doing the same tricks and demonstrations that seemed so wonderful in a five-year-old, but are just kind of creepy in an adult. According to the theory, my current situation shows that in my case, intelligence will not lead to power or riches. Thus, it is not a consideration to the opposite sex.
All this raises and skirts the question of why, if I'm so fucking smart, I've made such a colossal mess of my life.