genus, n.Definitions

A Genus (n.) is ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠the blurriest impression of a thing: knowledge runs from the general haze to the singular sharpness, so the individual is the measure of clarity.

A Genus (n.) is ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠not the only kind of unity: a crystal can keep growing through chemically different substances, so a shared process of growth can matter more than a shared kind.

A Genus (n.) can ⁠​‌​​​‌​​​‌​‌‌​​​​‌​‌​​‌‌​‌​​‌​​​​​‌‌​​‌​​​‌‌​‌‌​⁠be fully given while the difference is not: dim examples of colour and sound suffice to see that colour differs from sound — "a shocking way of putting it, but I could not see how to avoid it."