Chrysippus and his indemonstrables modes of reasoning

From the Jeremy Kirby's entry on Chrysippus in the IEP.

"...Aristotelian arguments above made use of classes. The ... relata herein are propositions [not classes]—Stoics called these ‘sayables’—rather than classes. In Aristotelian logic, the key connectives are ‘all’, ‘some’, ‘is’, and ‘is not’. In Chrysippus’ logic, the key connectives are ‘if’, ‘or’, ‘and’, ‘not’. "

Modus ponens: If p, q; p; ergo, q. : p→q, p, ∴q

Modus tollens: If p, q; not q; ergo, not p. : p→q, ¬q, ∴¬p 

Modus ponendo tollens: Either p or q; p; ergo not q.: p∨q, p, ¬q

Modus tollendo ponens-1: Either p or q; not q; ergo p.: p∨q, ¬q, p  

Modus tollendo ponens-2: Not both p and q; p; ergo, not q. ¬(p∧q), p, ¬q