Logarithmic nature of sensations
what we gain in breadth we lose in precision: we register the world’s stimuli in logarithmic rather than linear increments. For example, if you increase the energy of a sound’s volume by a factor of 10, your ears will judge this change to be rather small.
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Photoreceptors tuned to sun’s emission range
The energy emitted by the Sun, whose surface temperature is about 6,000 degrees absolute, includes plenty of infrared, but peaks in the visible part of the spectrum, as does the sensitivity of the human retina, which, if you have never thought about it, is why our sight is so useful in the daytime.
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