What does the world look like outside of our brains? © Getty Images

What does the world look like outside of our brains?

Without our brain, can we ever really know how to interpret all the sensory information?

Asked by: Nye Lewis-Davies  

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Your question has echoes of the American philosopher Thomas Nagel’s classic paper “What is it like to be a bat?” – a creature that is able to navigate using echolocation (by bouncing sounds off the environment). Nagel wrote that we can never step outside of our own brain and take the bat’s perspective on the world because we lack their sensory equipment.  

Likewise, one could argue that we can never know what the world ‘looks like’ free from our brains because we can only perceive objective reality through the veil of our senses, such as via wavelengths of light hitting our retina, or odorous molecules stimulating nerve cells in our nose. 

We can’t even ever truly know if the world looks the same from the perspective of another human brain. For instance, the colour that I label ‘red’ may subjectively look different to you than it does to me. 

We know as a matter of fact that there are aspects of physical reality that we cannot detect ourselves – such as radio waves, ultraviolet light (detectable by birds and bees, among other creatures) and high-pitched ultrasound (used by bats). And of course, there are likely many other aspects of reality not yet detectable by any creature or our most advanced technology – a possibility that fuels the imagination of science fiction writers and mystics alike. 

But while our take on the world is restricted by the limitations of our own neurological systems, it would be a mistake to underplay their potential. For starters, we have way more than five senses (among the other are balance, hunger and proprioception – the sense of where our body is in space).  

What’s more, recent research suggests that it may be possible for us to learn a form of echolocation, by making clicks with our mouths. Indeed, some blind people can already do this, using the echoes to piece together their environment as a bat would.

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