Talk:Vertical datum

Data and datums
I found (where my italicising distinguishes what Germans may call ''eine Mischung" (mixture), or if I recall correctly, "ein Mischwort";
 * in any case, commonly adopted criteria for '!vertical datums'' include the following approaches:
 * tidal, based on sea level at whichì specific conditions occur;
 * gravimetric, based on a geoid; or geodetic, based on the same ellipsoid models of the Earth that are used in computing a horizontal datum.  (It must be kept clear that those who write succeed (or fail to), at the task of elucidating their intent, when they utter that seemingly absurd construction, are neither knaves nor fools. So their mere absolution hardly suffices.)   A fundamental paradox is that "datum" (at least in Latin) is a noun, singular as to number, but  and also, that its plural is inevitably "data": significantly, the two languages' nouns are, respectively, plural, and mass nouns. And It matters very little how wise native speakers from Latia dealt with this conundrum. But the concept's true value lies not in an isolated datum, but in the relationships between and among (so called) "data points" (for the same reasons that vision so often provides good metaphors for comprehension -- alongside "grasping the point"  -- a  presumable invocation not of weaponry, but of the similarly precise points ''of view,  that result from reaching effective locations and directions for looking into, and gaining insight about, "re-presenting" various things. JerzyA (talk) 04:52, 24 November 2019 (UTC)