Wisdom from the Early Stoics, Zeno of Citium 43

Of propositions that are not simple, the hypothetical, according to Chrysippus in his Dialectics and Diogenes in his Art of Dialectic, is one that is formed by means of the conditional conjunction "If." 

Now this conjunction promises that the second of two things follows consequentially upon the first, as, for instance, "If it is day, it is light." 

An inferential proposition according to Crinis in his Art of Dialectic is one which is introduced by the conjunction "Since" and consists of an initial proposition and a conclusion; for example, "Since it is daytime, it is light." 

This conjunction guarantees both that the second thing follows from the first and that the first is really a fact. 

A coupled proposition is one which is put together by certain coupling conjunctions, e.g. "It is daytime and it is light." 

A disjunctive proposition is one which is constituted such by the disjunctive conjunction "Either," as e.g. "Either it is day or it is night." 

This conjunction guarantees that one or other of the alternatives is false. 

A causal proposition is constructed by means of the conjunction "Because," e.g. "Because it is day, it is light." 

For the first clause is, as it were, the cause of the second. 

—Diogenes Laërtius, 7.71-72