Light enables us to see the world around us. It provides the means by which our sense of sight gleans the most direct information about the physical arrangement of the world and how it is changing. Indeed, the capacity of light to carry and convey information is perhaps its most important, and remarkable, characteristic.
Seeing is believing
Sight enables us to locate ourselves in our surroundings, defining things outside ourselves that allow us to construct a true picture of the world. And sight inspires the imagination beyond the physical sensation of vision itself. George Richmond’s painting,
The Creation of Light, shown in Figure 1, illustrates the central place light has in our psyche. Indeed, words deriving from the idea of light-insight, illumination, clarity, for example-pertain to human, as well as physical, qualities. In fact, Latin has two words to describe light, lux and lumen, denoting both the material and the metaphysical aspects of light. It is the former with which this book is primarily concerned. The intertwining of the physical and the poetic has made light a metaphor for thinking about the world, in philosophy, theology, psychology, art, and literature. Because it is something of which almost everyone has direct experience, the physical basis of light and how it facilitates this powerful sense has made it an object of study for philosophers and more recently scientists, for centuries.
1. The Creation of Light by George Richmond.
Light gives life. Literally, light plays a vital role in the biological and chemical processes that underpin our and our planet's existence. Figuratively, light frames our perception of our surroundings. Our common everyday experiences illustrate the central importance of light in this regard. Of course we use it for illuminating our environment, either naturally, by the Sun or Moon, or artificially. Most common light sources use electricity, but on occasion we still use chemical reactions to generate light; burning candles, for example. The diferent character of the illumination has an efect on how we perceive our surroundings: it sets a ‘mood’ for the physical space.