Re: circular relationships ok?

Brian Selzer wrote:
[...]
>the existence of a tuple in R requires that exactly one tuple exists in S

... but it does not mean at all that set Br is the same as set Bs, so what is the biconditional 'iff' doing here ? Or if you are into fancy notation, it is true that

forall b (b in Br --> b in Bs)

but not necessarily true that

forall b1 forall b2 (b1 in Br <--> b2 in Bs)

unless you stipulate so. Received on Sat Mar 04 2006 - 17:34:52 CST