"If ... then ...", in the sense of "if X is true then Y must be true", could actually be communicated
in Spem with "ke ... zɪtu ke ...", but that's too slow, so I saw fit to add a shortcut.
"If ... then ..." should be translated as "ke ... ko ...".
"Because ... therefore ..." is also a way of saying "X entails Y", but differs from if/then in
that it asserts the premise is in fact true, and hence it asserts the conclusion.
I think it makes sense to translate because/therefore as " ... ko ...", just taking
out ke. You're saying, "This is true, and it entails the following", so it makes
sense to translate the first clause as unmodified from a regular statement and the consequence
just with the shortcut for zɪtu ke.
The causal if/then, as in "If you do X, Y will happen" (note this is a different
meaning from "If you do X, that entails that Y will happen") is ye/kyo.
I'm still very unsure of this doctrine. One concern is that it's wrong to use ke to
mean "if", because you could say like "that ... is ...", and it might be bad if you can't tell
the difference until getting to the second clause. Another concern is that in the because/therefore
form, there's no difference between stating something because it's your point and stating it because
it's a premise for your point, until you get to ko.
A potential third concern, though smaller, is that this system makes it not easy to state
the conclusion before the premise. Let me know in the comments if you have any thoughts on this.
Also, should zɪtu now be scrapped? Can ko take its place altogether without