John comes in colors.

Not literally, because that would be a side-effect of some Pegasus disease that didn't even bear thinking about.

He sees colors, bright and flashing behind his eyes. With Nancy, it had been the aqua-green of protection. With Teer, the glow of innocent white and fresh light yellow. Chaya had been dark green - envy and greed.

With Rodney, he sees blue.

The light blue of understanding, the dark blue of Rodney's endless knowledge.

The blue of Rodney's eyes and the perfect blue-white of the event horizon of the Stargate - the place where one step forward takes him everywhere.