2
Summary of Notions
r.e.
f
is a consequence
of
G
,
G
²
f
f
is deducible
from
G
,
G
`
f
co-r.e.
r.e.
Complexity
G
has a model
G
is consistent
f
is valid,
²
f
f
is a theorem,
`
f
Semantics
Syntax
