On Turning Ten by Billy Collins The whole idea of it makes me feel like I’m coming down with something, something worse than any stomach ache or the headaches I get from reading in bad light– a kind of measles of the spirit, a mumps of the psyche, a disfiguring chicken pox of the soul. You tell me it is too early to be looking back, but that is because you have forgotten the perfect simplicity of being one and the beautiful complexity introduced by two. But I can lie on my bed and remember every digit. At four I was an Arabian wizard. I could make myself invisible…