The shapes light makes in memory are subject to a Doppler shift. Clear at the centre, they become beige and blurred towards their peripheries. The very word 'memory' has a way of conjuring natural light. With an effort we can recall fluoresent strips in waiting rooms: the forensic light of testimony. Recall isn't memory. memory wants the past to be warm or bright as if no artifice could match the weather or flame.
But when light is recorded or depicted, then we forgive the artifice of painting and photography, and extend that forgivenness to artifical light. Instead we shift the content of memory from the light source to what it illuminates: Dietrich's face lit and shot by Garmes, or the thread of blue in the milk at the lip of the jug held by Vermeer's housemaid.
Like light that falls through bulls-eye windows or a wineglass, the transformation of light in space, like its translation through time, relieves memory of its obligation to condemn electricity. In such moments we realise that ther only ever partially recoverable image of light we have in mind is secret. It is ours because it cannot be shared, and for that reason is always tinged by a certain sadness. Whereas the light that is transformed in front of our eyes, by whatever trick or tool, is free to share and so liberated from the necessity of naturalising, a process whose goal is always to prove that one is One, and a self.
In the greatest nature poetry there is war against the fatefully personal memory of light ("a May-mess, like on orchard boughs"), a struggle to recall that may be as difficult as to bring to recollection the unemployment office in Deptford on a Tuesday at 11 o'clock in the spring of 1975. For GM Hopkins a similar difficulty frets and frames the 'random grim forge' of Felix Randall, hingeing undoubtedly on the priest's refusal to mourn the death of his unhappy desires, but for all that anchored in the blacksmith's fire and sparks. To bring that light to life and to the light of day was possible only because it mattered. It mattered that it not be lost, but also that it be extracted from the living tomb of personal memory. Poetry like photography is the enemy of memory, where memory sets itself againt communication.