What is the difference between logic and rhetoric?

Logic is more general and rhetoric is more specific.

Logic: the study and statement of the principles of good reasoning

Rhetoric: the study of persuasive discourse, especially argumentation

These definitions are not stone-set though, which means some may take it to mean something different.

imparadis't in one anothers arms  

the happier eden, shall enjoy their fill  

of bliss on bliss, while i to hell am thrust,  

where neither joy nor love, but fierce desire,  

among our other torments not the least,  

still unfulfill'd with pain of longing pines;  

yet let me not forget what i have gain'd  

from their own mouths; all is not theirs it seems:  

one fatal tree there stands of knowledge call'd,  

forbidden them to taste: knowledge forbidd'n?  

suspicious, reasonless. why should their lord  

envie them that? can it be sin to know,

the mending wall was written by robert frost