Women. Women are beautiful. And that's a problem if you're a bachelor who doesn't want to be bothered. Schopenhauer says that it's just the species trying to replicate itself. Beauty is nothing more than the will-to-live of the species shining through.
Exiting my apartment building this morning on my way to work, an icy fog hanging in the air, I looked across the street and there was a young lady, a trim vision of perfection in high boots, yoga-type tight pants and a pea coat. She was unassuming but stunning. There's something about the hip, posterior, thigh region of a healthy, well-formed woman that positively sings. And Schopenhauer is right; it must be all hard-wiring because the same anatomy on post-menopausal women is usually mute.
I also think the weather plays a role. It has been cold and icy the last week and except for one jog around the park last Saturday I have not run. And when this happens I notice that I become more distracted by women.