Re: Principle of Orthogonal Design

On 5 feb, 22:06, Marshall <marshall.spi..._at_gmail.com> wrote:
>
> However, suppose we have a binary predicate P over
> domain X and we want to assert it is reflexive? In predicate
> logic we can use the same name twice and express this
> very conveniently:
>
>   Ax in X: P(x,x)
>
> How would we do this if P's attributes were already bound
> to the names "x" and "y"?

Roughly the same, except you indicate the role in the predicate with the attribute names. So assume that attribute names are 'a' and 'b':

   Ax in X: P(a=x,b=x)

• Jan Hidders