We had had occasion, with one of the lunar mansions, to discuss the paradoxical importance of weaker stars and asterisms. Now, last week our reading had to do with the importance of the two poles (qutbayn) and their related stars: Polaris (al-Jāh) in the first place, but mentioning also Errai (γ Cephei) and, near the South Pole, the Magellanic Clouds. Ibn Mājid gives several ways of ascertaining the location of the poles using combinations of pointers, and then he observes,
The Pole is not with a given star, but it is a black space between east and west, which is ascertained with the astrolabe and the lodestone.
He goes on about this idea, and somewhere else in the text he says the Pole “is not clothed” or “wrapped” with any star. This fact is of course at the basis of the crucial technical concept of Polar Star calibration (bāshī), which was so important in Indian Ocean nautical sources; the need to know exactly the relation between Polaris and the Pole at any given time.
It is almost a truism to speak of the immobility of the centre of motion, like a wheel hub—it is after all the Aristotelian motor immobilis—and it is a given of any axis of movement. But this immobility does not require the invisibility of the axis, that it be somehow “imperceptible”, only within grasp of the mind’s eye, through reasoning and contemplation. This is exactly like the nature of all the celestial circles in an armillary sphere. It might be tempting to call them “figments of the imagination”, when in reality they are truths recognized by the imaginative faculty.
How many certain routes traced, and how many bright and prominent events accurately anticipated, all on the basis of these invisible polar certainties! Beyond simplistic stereotypes of “science vs intuition”, and beyond the media-fed storyline of science as the summit of exactitude, it is strikingly obvious here, as in other similar instances, that science has always been not only at ease with uncertainty and with opaqueness, but rooted in it. The scientist, like a sailor in the night, is at home with indetermination, again and again. Good to remember in these uncharted times, and quite in line with Hesse’s verse,
Wahrlich, keiner ist weise,
Der nicht das Dunkel kennt.
“Truly, no one is wise
Who does not know darkness.”
[JA]
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