The penis graffito is probably the oldest symbol in the world.

BTW, This is a close runner up: ({}).

There are many, many examples of the penis graffito, but for the sake of space (and sanity) we’ll just look at two from the Clinton-Washington G train stop. Both of them seek to impose sexual power on the person in the poster, and the only difference between the two — and it’s a slight one at that — is the gender object of the power.

Poor Moonshadow! He looks happy, but size of that member cannot be very satisfying.

Is it pornography? If it is, what can a concerned citizen do about it? Public decency is absolutely necessary — no one would argue it is OK for men to walk the streets wagging their membri viri at passersby. But how can you stop someone from stamping a symbol of male power on a poster in the subway? You could have the cops check everyone’s bag for Sharpies. Giuliani introduced paint-proof trains to get rid of unsightly graffiti. One rider took the matter into her own hands and attacked the vandals on their own turf: