Amazing how no non-Calvinist 'understands' Calvinism.
The problem in understanding Calvinism is that they want anything to mean anything.
Calvin stated very clearly that it was by God's will that Adam sinned, (and Calvin rejected the notion of a permissive will,it was all directive)
I admit that by the will of God all the sons of Adam fell into that state of wretchedness in which they are now involved (Institutes, Book 3, chapter 23)
I guess Calvin himself did not understand Calvinism!
;-)