Flies in your eyes.

As I gaze from my balcony across the countryside, I often see a swarm of flies, although not as many as in the photo!  Sometimes I track them, watching the group as it moves around.  Occasionally it will move towards me and just as I think it is within spitting distance (not that I would!), it disappears.  I have confirmed my sightings with my wife, who has also seen the flies and has been pleased that they have disappeared rather than landed!

Recently my wife visited the optician to collect some new spectacles and mentioned the flies only to have our observations shattered!  The 'flies' are 'floaters' - yes, what we have been observing are floaters, which are deposits of various size, shape and consistency, within the eye's vitreous humour, which is normally transparent.  The common type of floater, which is present in most people's eyes, is due to degenerative changes of the vitreous humour.  Sometimes, these floaters are called Muscae volitantes, which is Latin for 'flying flies'.  The objects exist within the eye itself and so are not optical illusions but are entropic phenomena.

Well that's interesting isn't it?!  Yes, I think it is.  The flies in my eyes were until recently, real flies.  Particularly as we live in a part of the world where, at certain times of the year, we battle against mosquitoes, which includes ensuring we have nets on all the windows and doors - but still the little buggers manage to get into the house!  So we have an awareness of the unwelcome presence of flying insects.  Whilst we have this in the back of our minds, why wouldn't we mistake floaters in the vitreous humour for flying insects?!

"Perception is Reality."

Albert Einstein said: "Reality is merely an illusion, albeit a very persistent one."  Douglas Adams said: "Everything you see or hear or experience in any way at all is specific to you.  You create a universe by perceiving it, so everything in the universe you perceive is specific to you."  So whereas my perception of the flies changed because of information my wife received from an optician, which I subsequently researched and confirmed, my perception could change again if, for example, another expert had an alternative plausible theory.  We can only base our view of specific situations and indeed, life in general, on what we perceive using our sensors.  But what my 'flies in your eyes' experience has demonstrated is you shouldn't always believe what you see.  As Douglas Adams points out, it is all specific to the individual observer.  If I should question what I see, then likewise I shouldn't necessarily believe what others tell me they have seen.  Yet everyday I watch the News and mostly believe what I am told.  How naive is that?

I will draw this post to a close with a quote from W. Edwards Deming: "Without data you're just another person with an opinion."  Wise words, but can you believe the data, even if you've seen it with your own eyes?!