| Description: Stoic logic Thema 2
version a.
Statement T2 of [Bobzien] p. 117 shows a
reconstructed version of Stoic
logic thema 2 as follows: "When from two assertibles a third
follows,
and from the third and one (or both) of the two another follows, then
this other follows from the first two."
Bobzien uses constructs such as 𝜑, 𝜓⊢ 𝜒; in Metamath we
will represent that construct as 𝜑 ∧ 𝜓 → 𝜒.
This version a is without the phrase "or both"; see stoic2b 1418 for the
version with the phrase "or both". We already have this rule
as
syldan 280, so here we show the equivalence and
discourage its use.
(New usage is discouraged.) (Contributed by David A. Wheeler,
17-Feb-2019.) | 