"The First Axis: The Aristotle/Theophrastus Boundary and the Voice of an Operation" is a paper by Lee Sharks (v0.7, 6 September 2026) that runs stylometry across the corpora transmitted under the two names and finds that the boundary the numbers draw does not coincide with the name-boundary. At the one seam where the texts are continuous on the page โ the Metaphysics fragment writing ฮ's hinge from inside โ the names sort the texts; in the biology and the doxography they do not: De sensibus is the nearest neighbour of the Parts of Animals and De caelo, and the Historia animalium is nearer the Historia plantarum than to Aristotle's own Generation of Animals. The line that predicts both is the operation: the Athenaion Politeia, a registry under Aristotle's name, has all three nearest neighbours Theophrastan; the Categories, ฮ and the Topics lean to the instrument; the Politics divides at book III; rolling windows locate the line at the chapter โ Metaphysics ฮ's survey against its critique of the Forms, the Ath. Pol.'s allotment machinery, ฮ 8's count of the spheres, the one world-voiced passage in the theology and the passage the fragment contests. With the names removed from the instrument, 400 blocks from 39 texts cluster by operation and leave the names at chance; the purest instances of the supposed Theophrastan voice are the Ath. Pol. and HA, under Aristotle's name; the first principal axis of the two corpora is the axis between the world (described or explained, and what people do) and the logical-metaphysical instrument. The paper's own programme is then run to completion: three feature families, one edition end to end, a blind reader's labels that located the boundary at the instrument rather than at explanation, a predictive test on fourteen held-out texts (11/12), a file erratum (Problemata and De coloribus, both spurious, landing by operation), elision neutralized, Lee's labelling rule (what a text treats and how), and the centre texts read at the passage. Nothing about hands, dates or membership is asserted; the paper states which account must now carry which burden. Extracted from the notebook The First Draft (#1585); companion to Aristotelian or Theophrastan (#1583) and The Registry Has One Column (#1584).