We adore lists. We think we know something about things or events if we can put them into an order. Not just as an aide memoire as you would expect using alphabetical, numerical or calendarian systems but a genuine belief that if we can put things into an order we have grasped something about them; gained some knowledge of their place in our world.
There is a tension in our knowledge between the objective world and how it works with us in it, and our subjective understanding. Just as we have come to see mathematics as a tool with which we can unlock knowledge of the Universe, and as we do so we find the knowledge we need ever increasing, so we should see our brains are also a tool – and we all have different skills in our usage. We all see the world slightly differently. The differences may not be vast but like DNA they don’t have to be to make wide and varying differences in what we think we know.
Just because we can place something in a list that accords with our understanding does not mean we have begun to understand that thing at all. We can say we have a knowledge that something exists we can list. Numbering animals, collecting insects, is not to know anything.
It is just one usage of our brains.