In folio K/P 143v, which opens the series of hand-dissection reports, Leonardo proposes seven phases from the osteological study to the «hand clothed with skin», and specifies that the whole should be repeated for «an old man, a young man, a child, and for each shall be given the measurement of the length, thickness and breadth of each of its parts». The full plan would then comprise hundreds of drawings. In the last passage of the note on the hand in the ordine del libro page, Leonardo decrees that this mode of presenting the data acquired by dissections be employed for every other member, and concludes the aspired-for program with the most intriguing single word in his vocabulary: ecc.

The two sections of the page constitute two poles of scientific pursuit. I would say that for Leonardo, the insistence on the concrete, endlessly explored particularity of the hand is discursive: it presupposes a first-person mode of involvement, whereas the numerological plan belongs with the language of authorless narration (a relation that in today’s science would be inversed). But why at all does the hand occupy such a privileged place on this page, when the work-plan is concerned with systems rather than with organs? And how to explain this minute attention to actual hands, so different in spirit from the schematic, culturally-correct, quasi-numerological agenda that the main column of the same page unfolds? Finally, why does the incessant research of the hand, including its external morphology and life-cycle, serve as a model for every other member?

My suggestion is straightforward: because the hand represents the body, and at the same time defies closure. Aristotle has written that «the hand is not one organ/instrument, but many», since it is «the instrument of further instruments». [25] Leonardo’s approach to the hand entails a considerable amplification of this pragmatic notion. For him, the classic definition means that the essence of the biological hand is handedness, namely, its living operations, which cannot be reduced to its mechanisms – despite the scientist’s passion for a reductive, ritualistic transparency. Guarda se tu credi…

The Music-Making Hand in Light of the Rivalry of the Arts

The professed objective of the Parte prima of the Book of Painting (Codice Urbinate 1270) is, famously, the exaltation of painting (and more ambivalently, of music) and the disparagement of poetry and sculpture within one and the same system of value parameters. [26] At issue are disparate modes of capturing otherness through facture, thus quasi-possessing it and triumphing over it ― doomed as this otherness is to contingence and decay. At issue are gaps, transferals, displacements, and the frustration of an ever-deferred appropriation: indeed, the evanescent opacity of otherness as such.