Author’s note: It’s been a while since my last review from Alister McGrath’s The Intellectual World of C.S. Lewis; simply put, life. All quotes in this post, unless otherwise noted, from the fourth chapter/essay of McGrath’s book, pages 83-104.
The library of C.S. Lewis’s work has received a lot of attention over the past century, but according to theologian and Lewis expert, Alister E. McGrath, there has been “surprisingly little attention” paid to his preference for analogies and metaphors “relating to sun, light, vision, and shadows in his writings.” ‘The Privileging of Vision: Lewis’s Metaphors of Light, Sun, and Sight’ is the fourth chapter and essay from McGrath’s The Intellectual World of C.S. Lewis, and seeks to begin remedying the lack of scholarship dedicated to investigating Lewis’s preference for ocular metaphors in his writing.
Most memorably is his use of “illumination” to explain the truth of Christian Theology above Pagan mimicry in his magisterial essay, delivered to the Socratic Club at Oxford University in 1945, entitled ‘Is Theology Poetry?’ Lewis, in answering the question, “What light is really thrown on the truth or falsehood of Christian Theology by the occurrence of similar ideas in Pagan religion?” explains that,
“Theology, while saying that a special illumination has been vouchsafed to Christians and (earlier) to Jew, also says that there is some divine illumination vouchsafed to all men. The Divine light, we are told, “lighteneth every man”. We should, therefore, expect to find in the imagination of great Pagan teachers and myth-makers some glimpse of that theme which we believe to be the very plot of the whole cosmic story—the theme of incarnation, death and re-birth.”
However, it is “the conclusion and the climax” of Lewis’s essay that drives home the point of both his argument, and his preference for such ocular imagery:
“I believe in Christianity as I believe that the Sun has risen, not only because I see it but because by it I see everything else.”
In tracing the foundations of Lewis’s preferences for ocular imagery – specifically “Lewis’s clear preference for visual analogues for human thought” – McGrath ably and briefly covers the historical examples for analogies, primarily ocular, as well as audible. Specifically, McGrath highlights that “Protestantism’s characteristic emphasis upon the foundational role of the ‘Word of God” leads to a corresponding preference for auditory metaphors.” Specifically, Martin Luther was particularly fond of auditory metaphors, in which “faith arises from hearing the Word of God properly” while, “for Lewis, faith expresses itself in seeing things rightly.” More in line with Lewis, therefore, was Augustine of Hippo, “who made the imagery of light the cornerstone of his discussion of true knowledge, especially knowledge of divine things.” McGrath posits that of the many “glad debts” Lewis felt he owed to Augustine, “The notion of divine illumination … would be one of them.”
For Lewis, many of his writings made a lot of the metaphor of the sun illuminating knowledge. Not only did Lewis consider that “the Christian faith offers us a means of seeing things properly – as they really are, despite their outward appearances” – especially noticeable in Lewis’s The Pilgrim’s Regress – but it also played a significant role in his own rationalist outlook on life. Specifically, Lewis doesn’t see human reason as a source of light in and of itself, but rather that “the ability of reason to illuminate things is itself a consequence of it already having been illumined by the Divine reason.” Reason doesn’t exist as something humanity has achieved, but as something which has been bestowed upon humans by God – reason is illuminated.
Lewis, according to McGrath, clearly believed that metaphors of light and the sun and illumination were not only “well grounded in Christian tradition,” but that they subsequently echoed throughout Lewis’s first love, classical philosophy, because of their solidity in Christian truth.
 Screwtape Proposes a Toast and Other Pieces, C.S. Lewis, p. 49 (1974)
 ibid, p. 50
 ibid, p. 58