Here is an inference rule called Modus Ponens.

               
                A   A -> B
                ----------- (Modus Ponens)
                    B

Here is a derivation tree using Module Ponens.

                 A /\ B
                -------
                   A     A -> B
                ----------------
                       B

It's kind of like a CS upside down-tree, or like a normal or real tree, where the branches go up.

Is this layout already possible? This feature alone places this tool as a competitor to other Mathematical tools for logicians, it's best if it's not a plugin or something that users have to build themselves. Logicians will unfortunately just use Latex if they find it too hard to get this result.

If this facility already exists or it's easy to add, please excuse my ignorance. Thank you for your effort! I appreciate it!

Warm regards,


Sinanmo