As we know, philosophically, if a tree falls in the woods and it falls on the only person who was there to hear it, the tree wouldn’t have made a noise when it killed them – presumably because it would be trying to sneak up on the blighter.
Or something. Welcome to the wonderful world of perception. At an evolutionary level we humans tend to think of ourselves as pretty special. And yet from what we know about perception that isn’t true in all ways.
Take birds for example. Many birds “know” which way is North. They don’t have to think about it. They don’t have to take out their compass or whatever, they just know. The same way you know which way is down or the same way you know when it’s dark or light. You don’t have to think “oh, it’s dark”, you just know. That’s perception.
Now in this example we’re pretty sure that we agree with birds where North is. And so it doesn’t feel that weird knowing they can sense it.
But what about hummingbirds? They can see infra-red as a colour. Now, in theory we can see infra-red too. But of course infra-red isn’t red in just the same way that green isn’t red. It’s another colour and we can’t see it and they can. They don’t turn on their infra-red vision to see it, they just see it. And we never will. Because to make it visible to us we have to turn off the other colours and substitute something else (red).
So we can see that the world isn’t necessarily as we perceive it. The world isn’t the way a human sees it where the other animals are getting it wrong. The world has never truly been seen by anything. We just happen to see it and sense it in one way.
Back to the hummingbird. The hummingbird also perceives the world more slowly than we do. If you were jogging along, the bird would perceive you as moving slowly compared to everything else. That’s why birds seem to move out of the way of cars far too late. Even time is not constantly perceived. We know that we can measure its progress, but what does it mean if we know we aren’t perceiving it at the same speed as anything else on our planet?* To birds we are lumbering slow moving things, like elephants seem to us.
So why are we so sure of ourselves? Unless you’re really thinking about the issue people find it very difficult to think that the world might not be as they are perceiving. The answer is, of course, evolution. People who were constantly questioning what they perceived have been deselected. If you approach a lion wondering if it really is a lion you might not live long enough to have so many children.
We’ve been hearing a lot in the last few years about scientists attacking religion (Richard Dawkins, for example) and while I’m not religious, I really think science is being badly misrepresented. The best way to make people question their devout beliefs is to show them things like this. Now you might have read this and seen it as a confirmation of God’s splendor and mysterious ways. But I like to think that subjects like this remind us that you shouldn’t really believe received wisdom, especially not the received wisdom of your own brain or upbringing. Go and find out for yourself.
Just quickly, I’d like to tie this back to the subject of Free Will I discussed last year. Hopefully you can see why many scientists and philosophers believe that free will is an illusion of a similar kind to time and vision. It is useful to believe that we are consciously in charge of what we’re doing, but we might not be. And if that doesn’t make you question what’s going on in the world, then I don’t know what will.
*surely there’s a low chance those aliens we meet in sci-fi are actually all going to perceive time at the same rate as us – but I imagine it would make conversation a bit difficult.