It
means that if you have both a disjunction
P1 v...v Pn
and the right number
of the right sorts of subproofs, then you are entitled to enter
a given sentence, S.
The right number of the right sorts
of subderivations?
Yes.
For each disjunct, each Pi, you need a subproof that
starts with Pi and ends with sentence S.
You will need to cite the disjunction and each subproof.
