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"You see no difference?" The cloud appears surprised, "Let's ask ourselves, how is the visible spectrum of wavelength defined?"

The sun and the rainbow look at each other in a vacant expression.

"The visible spectrum is defined by people's eyes," the cloud goes on with his lecture, "And eyes are the product of evolution - they are meant for detecting signals of electromagnetic waves that could pass through the atmosphere. In other words, the sequence is not people could see certain things, the air is transparent, and therefore people could see everything. What actually happened is the atmosphere filters off a whole lot of signals and moulds the eyes over the years, so that people could only see what they are allowed to see - and they have no idea what they have left out."

The sun remains silent for a long while, and then he says slowly, "That sounds a brilliant strategy of management - or leadership."

"Yes. Of course it depends on who uses it."