Define one as anything not made of things so smooth and small they pass between themselves, nor so sticky that they grab and won’t let go. This is why a glass made of glass is useful,

both for holding a drink and for drinking it: liquids that for their own reasons don’t mix, like oil and water, or orange juice and Scotch. The first can be flicked into the fireplace

as the second walks backward down your throat en rappel, with wire rope and thumbtack cleats, a hazardous move when executed in reverse: this is the essential element of the phase,

the recursive triple entendre, with duck dive and backhand chainsaw pass. Liquid’s not solid, you might say, because it can still say anything. And it isn’t gas: because it must say something.