Upside down E was Re: Mathematical Symbols

[Barbara Need]

Quoting "Baker, John" <JMB at STRADLEY.COM>:

>         It's easier to understand what Barbara Need is saying if you imagine
> a capital F instead of a capital E.  The right-side-up F has bars in the
> middle and top of the letter, pointing to the right.  What would an upside
> down F look like?  If the paper is simply rotated on a vertical axis (i.e.,
> the paper remains flat on the desk and is turned around, or the viewer walks
> to the other side of the desk), the two bars of the F, now at the middle and
> bottom of the letter, will point to the left.  But I think of an upside-down
> F as having bars that point to the right, just as they do when the letter is
> right-side-up.

> John Baker

That certainly helps. But for me, a rotation on the vertical axis would involve
lifting one edge of the paper and turning the paper over! In such a scenario,
the previously top bar of the F is still at the top but pointing left (in
scenario described above, which is also Larry's) the "top" bar is now at the
bottom and pointing left. For me turning the E or the F upside down results in
the bars still pointing right, but, in the case of the F, the top bar is at the
bottom.

Barbara

>
>
> -----Original Message-----
> From: Laurence Horn [mailto:laurence.horn at YALE.EDU]
> Sent: Thursday, February 20, 2003 12:03 AM
> To: ADS-L at LISTSERV.UGA.EDU
> Subject: Re: Upside down E was Re: Mathematical Symbols
>
>
> At 9:42 PM -0600 2/19/03, Barbara Need wrote:
> >
> >My first thought was: wouldn't an upside down E be identical to a
> >right-side up E? But then I thought, when you look at someone's
> >writing "upside down" it is the reversed E, because the writing is
> >also right to left FROM YOUR PERSPECTIVE. But when I turn something
> >upside down, I usually only rotate on a horizontal axis, not also on
> >the vertical one. Is this the usual sense of turn something upside
> >down?
> >
> I don't know; this is too complicated for me.  I write a
> right-side-up E on a piece of paper and I turn the paper upside down
> and I get an existential quantifier, not the E that I started with.
> (Works with computer monitors too.)  Don't know from perspectives and
> axes, but that's how I do it.
>
> L
> ht-side up E? But then I thought, when you look at someone's
> >writing "upside down" it is the reversed E, because the writing is
> >also right to left FROM YOUR PERSPECTIVE. But when I turn something
> >upside down, I usually only rotate on a horizontal axis, not also on
> >the vertical one. Is this the usual sense of turn something upside
> >down?
> >
> I don't know; this is too complicated for me.  I write a
> right-side-up E on a piece of paper and I turn the paper upside down
> and I get an existential quantifier, not the E that I started with.
> (Works with computer monitors too.)  Don't know from perspectives and
> axes, but that's how I do it.
>
> L