Wipe Out; Learn; Repeat

Some of the lunar mansions, as we have seen before, are of no practical use, but only useful theoretically. That is, quite paradoxically, shiny objects in the sky which are important in spite of their invisibility. They are useful as “placeholders”, like the contours of a glass, perhaps, which are important as limits and containers.

Speaking of one such mansion, al-Na‘a’im, no. 21, Ibn Majid speculates of someone who might have devised a new personal method to use them for navigation, a method which then disappeared (yandarisu) after the inventor’s death, and he concludes: “There isn’t any good in altitude measures that are not put to use.” Let us dwell on the triliteral root (d-r-s) used for the “disappearance” of knowledge, because it combines two apparently opposite meanings of “erasing” and “learning”, and in so doing it illustrates key aspects of knowledge transmission. For example: dars means both “a lesson” and “effacement”—the image is that of the wind blowing signs on the sand, or a teacher wiping out a blackboard.

Like with a glass, where emptiness is a pre-condition of fullness, it seems that a certain kind of erasure is a prerequisite of learning. Science, understood as an accumulation of knowledge through the ages, is built on ignorance, we could say, and not only as an initial mythical tabula rasa, but as ever ascending and ubiquitous instances of unknowing. One apt image for this is the unknown sign, the x in an equation, “what is sought” (al-matlūb), in Arabic.

Another image is the vastness of space, which attracts the explorers and provokes their quests, time and again over the centuries. Two aspects of unknowing: the disappearance due to a break in the transmission is like a vacuum, sterile, an extinguished fire; while the burning “ignorance”, the open question, the “hope” for lands of legend, is an ever-receding horizon, like a plenum and a “matrix of all possibilities.” [JA]