[r-t] Definition of a peal

[Don Morrison]

On Tue, Aug 5, 2008 at 1:18 PM, Graham John <graham at changeringing.co.uk> wrote:
> Yes, it is change ringing, but is it true?

Well, defining "true" is what we're trying to do here, isn't it?

For now, let's assume that however we define "true", our definition
must be such that if the Council today would accept something as a
peal, then it has to meet whatever test we devise for "true". That
seems reasonable to me, at least.

If we further accept the theorem, of great usefulness, that a rotation
of a true round block is guaranteed to itself be true, then yes, that
the mixed extent block under discussion certainly is true: the Council
today is happy with six extents of Bob Minor and six covered extents
of Bob Doubles being called a peal, and thus should be covered by
however we define "true". If we apply the theorem, then rotating that
to start and end in the middle of one of those extents must also be
true.

> think about how you would write a program to test for truth. To be able to
> do this you have to define the stage.

Yes. At any point during the ringing, the band is claiming to be
ringing something of a particular stage. If your software can't deal
with that, you need to fix your software, or use someone else's. To
say "we can't allow this because it would make writing our tools too
difficult" is exactly what got us into the current prescriptive
situation. Our current intellectual tools were not up to describing
what some people have rung, and what others would ring if they didn't
feel it was prohibited, but the Powers That Be currently resist fixing
those tools. Software tools are no different.

Suppose you were getting a driver's license, and the clerk said "I'm
sorry, sir, you are not allowed to have that name. Our software knows
'John' is a first name, and you are not allowed to have it as your
surname. You cannot be Graham John." I think you'd be miffed. And
would rightly assert it's their problem and they need to fix their
software, it's not your problem and you have no need to "fix" your
name.

Yes, there is certainly some ambiguity. At any given point a band
might be ringing variable cover, or might be ringing pure doubles, and
whether or not it is true depends upon which they're doing. But we
have all sorts of similar ambiguities already, and have to honor what
the band says they are actually doing: is it Single Court Minor or
Original Minor? Is that a bob lead of Cambridge or a bob lead of
Primrose? Is that an extent of spliced Cambridge and King Edward with
only lead end bobs, or just an extent of Cambridge but with half-lead
bobs, too? Which is the right way to look at these issues is a matter
of context, and it's usually up to the band's judgement to define that
context.




-- 
Don Morrison <dfm at ringing.org>
"For love is like a tree, it grows of its own accord, it puts down
deep roots into our whole being, and often continues to put out
leaves over a heart in ruins."
             -- Victor Hugo, _Notre Dame de Paris_, tr John Sturrock