International Year of Light: a thought for Easter

In case you have not seen it yet, the United Nations General Assembly has declared 2015 to be an International Year of Light and Light based Technologies, with the acronym IYL2015. A Youtube channel dedicated to the opening ceremony for the year, which took place at UNESCO headquarters in Paris in January, can be found here. The UK Institute of Physics is one of the founding partners for the year - their homepage for the IYL2015 is here.

IYL2015 is clearly of particular interest to the scientific community. But if you look at the home page for the year linked above, it should be clear that the protagonists of the year have much wider interests. The headings as you scroll down the home page certainly include aspects that might be described as being more purely scientific. But there are included among the headings others that clearly indicate a cultural dimension to the use of light and light based technologies. A page  dedicated to Art and Culture, for example, refers to a range of fields in which light or colour plays a part. (Interestingly, this page includes  reference to stained glass, largely used to represent Biblical images). I would also include within the cultural dimension - perhaps because it is more immediately "human" - the page dedicated to Light for Development. The page on Study after Sunset is, I think, of particular significance here, and highlights how new developments in LED lighting make possible, with appropriate commitment of resources, a major impact on the cultural life of less developed nations.

The IYL2015 has a blog: light 2015blog.org.

I am prompted to post on the subject by the "Critical Point" article in the April 2015 issue of the Institute of Physics' magazine Physics World, which discusses the reaction to Isaac Newton's 1704 publication of Opticks. The article opens:

Until the end of the 17th century, writes art historian Kenneth Clark, artists thought of light as "an act of love", for it seemed to reveal, brighten and intensify nature. Light was the principle of epiphany, the self-disclosure of the world and its beauty.

Isaac Newton's famous 1704 book Opticks seemed to massacre that picture. Subtitled A Treatise of the Reflections, Refractions, Inflections and Colours of Light, it saw Newton treat light as just a mechanical phenomenon governed by mechanical laws. Colour is subjective, a sensation produced after light rays strike the eye. Sunsets, rainbows and moonbeams are explained by geometry in action, followed by the brain in motion.

The article continues to consider a response to Newton's work: Johann Wolfgang von Goethe's Theory of Colours. If one can attempt to summarise Goethe's intent it was to preserve something of the human, or cultural, understanding of the nature of light that had preceded Newton's work. The article ends with the following paragraph, to which I have added the bold:

Still, Goethe's polemics fascinate because he seems to champion a way of doing science that is different from the "usual sense". Science, then and now, is often pictured as an activity that's mostly about postulating "correct" mechanisms underneath phenomena, rather than about discerning phenomena in the first place. As the philosopher Ernst Cassirer wrote, "The mathematical formula strives to make the phenomena calculable, that of Goethe to make them visible". The problem is that the first way threatens to drive out the second. Goethe inspired those who viewed his anti-reductive approach - colour is a human, not a spectroscopic, phenomenon - as rescuing not only the science of colour, but an entire way of being a scientist.

The thought for Easter? Perhaps the most vivid moment of the Easter Vigil liturgy comes when the new light of the Easter Candle is processed into a Church that is otherwise in darkness - the symbol of the light of the Divine life of the risen Christ overcoming the darkness of sin. In the Liturgy of the Hours, there is another dynamic of darkness overcome by light that is played out daily. At Night Prayer, the Nunc Dimittis with its antiphon sends the Christian people to sleep after the manner of Christ's sleep in the darkness of the tomb represented by the darkness of night. And it is the moment of the next dawn - the coming of light - that they rise again to mark the time of the day that is particularly identified with that of the Resurrection.

For the Christian believer, light is at once a scientific phenomenon and a human phenomenon; and as a human phenomenon it has a supernatural dimension in our culture as well as a "secular" dimension, a supernatural dimension that is determinative in consequence of some two millennia of history.