Upside down E--another argument

[Tom Kysilko]

Recourse to technical language is a fine thing if ordinary language is ambiguous
or breaks down in some way.  But I'd hate to have rely on it for everyday
communication.

In the case of the upside down E: consider that this character first appeared
when type was still set.  Rather than having to cast type for new symbols, it
was easier to take an existing piece of type and turn it over before placing it
in the tray.

But if you want to get technical.  In transformational geometry it is recognized
that transformations in a plane that preserve congruence must be some
combination of:
1. translation (think of dragging an icon around on a computer desktop)
2. rotation about a point
3. reflection across a line

"Upside-down" is disambiguated by distinguishing between 2 and 3.  Curiously,
"backwards" doesn't have this problem.

--Tom Kysilko

Quoting sagehen <sagehen at WESTELCOM.COM>:

> A lot of this discussion of "backwards" or "upside down" might have been
> obviated by using the words "rotate clockwise (or counterclockwise)" which
> immediately both establishes  the plane  and keeps the  action planar.
> Not as picturesque as standing on one's head in the eye clinic, though.
> A. Murie