Some animals are capable of visualising a reward that exists in the future. For example, the scrub jays can hide food in a cache to retrieve at a later date. They can even rehide if they become aware that a potential thief has been watching them. 

This means they can see the world from a different perspective. This ability to see yourself in the position of others is vital to outsmart a competitor or empathise with a hungry friend.

Language takes the ability to read minds to a new level. Words enable us to think about ourselves and our place in the world and even about consciousness.

The original function of consciousness was probably to direct a mobile self to a fresh supply of food. 

Consciousness is dependent on vision. Vision adds context and depth to our world.  It adds a new dimension to awareness. 

The next step is to visualise food in its ...