On Monday, December 3, 2018 at 8:19:44 AM UTC-7, Paul Schlyter wrote:

Simple, isn't it? All you have to think about is to match your
selected type of day to the appropriate type of hour.

Perhaps. But I think that even though Oriel is a very special case, ordinary
people might come away from an attempt to teach astronomy with such brutality -
I'm thinking of the phrase "the brutality with which mathematics is... taught to
the innocent" - muttering that those astronomers are nuts.

In ordinary language, a day is 24 hours, and whatever a period of 23 hours and
56 minutes may be, it is definitely not a day, as it's four minutes short of a
day. Whatever you do, don't begin by flatly contradicting the meaning of words
in ordinary language - that comes across as making a statement that is *false*:
_because statements in a given language are understood by taking the words in
them, and replacing them by their meanings_.

So it's almost as if "a day is 23 hours and 56 minutes" *becomes* "a solar day
is 23 hours and 56 minutes" somewhere between one's eyes and the part of one's
brain that actually is aware of reading the sentence, if one is not already an
astronomer... I don't know if this makes sense, but it's as close as I can come
to explaining this. (Or, perhaps more directly: people expect words in anything
they read to mean what they *expect* them to mean - _new_ words, or even new
meanings for old words, can be introduced, and used subsequently, but don't
expect people to backtrack and put the new meanings in what they've already
read.)

Therefore, in statements on this matter addressed to the general public, you
should begin by using the term "day" only in its ordinary sense of the solar
day, and subsequently introduce the term "sidereal day" as a special technical
term by astronomers.

Failing to do this - failing to come out of one's ivory tower when talking to
those outside - is just what leads to confusion like Oriel's, even if most of
those so confused simply ignore astronomy from then on, instead of building a
whole system of "corrected" astronomy and then advocating for it while all the
time blindly refusing to examine one's own original mistaken assumptions and
confusion as he does.

So I think a careless legitimate astronomer is a little bit to blame for getting
him started, although he is now responsible for his own failure to change course
and understand what was explained to him wrong once, but which has now been
explained to him correctly many times over - by me alone, as well as by others.

John Savard