-tuhs +coff On Thu, Dec 23, 2021 at 11:47 AM Dr Iain Maoileoin < iain(a)csp-partnership.co.uk&gt; wrote: I totally agree. My question is about language use (or drift) - nothing Language change is inexplicable in general. About all we know is that some directions of change are more likely than others: we no more know *why* language changes than we know *why* the laws of physics are what they are. Both widening (_dog_ once meant 'mastiff') and narrowing (_deer_ once meant 'animal') are among the commonest forms of semantic change. In particular, in the 19C _arithmetic_ meant 'number theory', and so the part concerned with the computation of "ambition, distraction, uglification, and derision" (Lewis Carroll) was _elementary arithmetic_. (Before that it was _algorism_.) When _higher arithmetic_ got its own name, the _elementary_ part was dropped in accordance with Grice's Maxim of Quantity ("be as informative as you can, giving as much information as necessary, but no more"). This did not happen to _algebra_, which still can mean either elementary or abstract algebra, still less to _geometry_. In addition, from the teacher's viewpoint school mathematics is a continuum, including the elementary parts of arithmetic, algebra, geometry, trigonometry, and in recent times probability theory and statistics, for which there is no name other than _ mathematics_ when taken collectively. What was taught in the latter?