New ethics stuff!

Please start on p. 38 of this PDF of Plato's Republic, which is page 15 in the page numbers of the scanned book, and read to the end of p. 47 of the PDF which is page 24 in the page numbers of the book. 

Thrasymachus said that justice "is nothing other than the advantage of the stronger."  Do you agree?  Why or why not?

Does having the ability to do something make it morally acceptable to do that thing?  Put differently--if you can, may you?  Why or why not?

Please respond to these ideas in a post on the blog by Monday at 9:00 PM.  Thanks!