Types
•In classical model theory an
m-type for m ¸ 0 is a set t of
formulas with m free variables x1,
…, xm s.t. there exists a
structure A and m constants a = (a1, …, am) s.t. t =
{f | A ² f(a) }
•
•In finite model theory this is two strong: (A,a) and (B,b) have the same type iff they are isomorphic (A,a) ' (B,b)