Do Fish See the Water?

The words, 'The birds don't see the sky, the fish don't see the water and the human don't see the Earth' do suggest to me deeply philosophical ideas.
What I see are in fact two fundamentally different approaches to the branch of philosophy that Aristotle called 'First Philosophy', which came to be known as Metaphysics.

What does it mean to say that the fish doesn't see the water? We know that water is only a part of the world. For the fish, however, the world is the water it swims in. The analogy suggested here is that human beings believe that the world in which they live, the world of Earth, water and air — or planets, solar systems and galaxies — is 'all there is'. Metaphysicians from Parmenides and Plato onwards have argued that this belief is wrong. There is another 'world', outside space and time, which is in some sense the 'ultimate reality'. A well known example of this view is the belief that there exists a God who views the universe 'under the aspect of eternity'.