Sunday 29 April 2018

Episode 96 - 20/20 Vision


On Saturday something most surprising happened. It was sunny. Sunny enough to wear my sunglasses. I didn’t wear my glasses however, because it hadn’t occurred to me that it might be sunny enough for me to need them. Truth is I forgot I even had them. But it did start me think about how great sunglasses are, and in particular, how great my sunglasses are. When it’s too bright, too much light comes into our eyes and it becomes difficult to see – ironic huh? But Sunglasses stop some of the light getting to our eyes so that we can see more clearly. Genius! Simple but effective. Or are they? Whilst these kind of sunglasses help in bright conditions, they don’t do anything to help prevent glare from reflective surfaces. That’s why my sunglasses are so great! (Yes I know I’m starting to sound like a sunglasses salesman, but stick with me…)
The problem is that the light which passes through simple sunglasses like these remain incoherent. Uh huh, that’s right. Incoherent light. That’s a thing. I bet you wish I was being a little bit more coherent right now. Okay then, if you insist, let me grab my metaphorical geek lab coat and explain. When we see stuff, we can see it because light travels from it to our eyes. But that light doesn’t travel in a straight line, oh no, that would be far too simple! It travels in wiggly lines (that some boring people like to refer to as waves). Presumably it travels in wiggly lines because it’s following satnav, I don’t know. So instead of going in a straight line it also wiggles left and right. At least some of it does. Some of it wiggles up and down. And all of the rest of it wiggles at a variety of angles in-between the two. This angle of the light’s wiggle is known as its polarisation.
Any object that we can see has lots of light traveling from it to our eyes. All of the light coming from an object in normal sunlight will have loads of different polarisations – that is to say that although all the light will be travelling in the same direction, the wiggles will all be doing different things and it’s this which causes glare. What’s so amazing about my sunglasses is that they’re polarised, which means they act like a pair of bouncers at a very high end night club for rays of light, and only allow light whose wiggles are in a particular direction to pass through. As a consequence they reduce glare and allow me to see more clearly.
Sometimes life feels like it’s too bright and like all of the wiggles are pointing in different directions. There seems to be so much going on and there are so many voices speaking at the same time that I struggle to really see what’s happening clearly. Sometimes it’s hard to know what I should be doing or what I should believe. Sometimes I wish I had a pair of polarised lenses for life to make it all easier to understand. And as I thought about this for a while, I realised that I do, although not as visually obvious nor as easy to explain (yes that was the easy explanation). In the Bible, God promises that He gives His Spirit to all who choose to follow Him. And that His Spirit will help guide us when things get cloudy (or in this analogy sunny). I guess the truth is that too often it doesn’t occur to me that I need it or even worse I even forget that I have it, but life sure looks better when I’m wearing my Holy Spirit Sunglasses!

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