Education is a never-ending process – or should be. And what we learn depends largely on what catches our imagination. Not long agoI learned something by chance that changed the way I look at the world. Like many people, I grew up with the idea that the light by which we see things emanates from a source, bounces off the thing I am looking at, and collides with a cell in my retina. Not true, apparently. When a photon hits something, it is absorbed. This energy is then radiated back again as light: not the same photons, but new ones. In a way, then, the whole world is glowing. The leaves on the trees are alight. Your eyes are (almost literally) shining like stars.
Such a world is much more alive, more beautiful, it seems to me, than the passive, lumpen world I previously inhabited. Matter is active in revealing its colours and shapes to our eye. I think St Denys would have appreciated this. The way light is passed on by matter is an analogy for the way spiritual illumination is passed down his hierarchy of angels: each angel makes the light his own, and illuminates the others by his own gift. It also echoes the pattern of the Trinity, the supreme three-dimensional act of love. In love each gives to the other, each receives from the other. When we see anything, it is because a photon has been received, and a photon given. Light is gift.
