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Verbal diarrhoea
Tom Giles at BD Solutions has aided us in our MSDN confusion. Last week Grant Bowen said: ‘If the binary predicate is irreflexive, antisymmetric and transitive, and if equivalence is transitive where two objects x and y are defined to be equivalent when both f(x,y) and f(y,x) are false’.
Tom replies: ‘Binary predicates such as = and <, are reflexive, meaning “applies to itself”,’ he says. ‘So = is reflexive. Symmetric means reversible, so = is symmetric.
‘Transitive means it “carries over”. So = is transitive because if x = y and y = z then x = z. If two objects are equivalent when both f(x,y) and f(y,x) are false, then for a third object z (where f(y,z) and f(z,y) are also false), f(x,z) and f(z,x) must be false.
‘Basically, if f does not relate to x and y, and does not relate to y and z, then it does not relate to x and z either.’
So that’s clear. We think. Can anyone explain the explanation? Six words or fewer, please.
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