Except that you can come up with a decent definition of "fish" and "quadruped", whereas there's no definition of "tree" that covers all the cases. https://www.

Except that you can come up with a decent definition of "fish" and "quadruped", whereas there's no definition of "tree" that covers all the cases. https://www.theatlantic.com/science/archive/2018/04/how-do-you-define-a-tree/557135/ https://www.theatlantic.com/science/archive/2018/04/how-do-y...