Particle P

[chaletian]

Ah, how I giggle. All that talking of person A and person B made me think of the joys of Mechanics during A-Level Maths. You do a lot of stuff to do with motion and forces in Mechanics (OK, yes, it's almost all to do with motion and forces), and thus have pretty much always got a particle swinging in a pendulum or being pushed up an incline or falling out of an aeroplane (what? it was brilliant!), and the particle was invariably labelled "P" for ease's sake. And Catherine and I got bored with this, and thought this forced anonymity was a bit rough on the many particles we encountered, and thus renamed them. So we had particle Peter being dropped off a cliff and particle Pamela being thrown in an arc and particle Patricia sliding across a frictionless ice-skating rink. It was lovely. Happy days.