That seems extremely deceptive. The Free Software movement is a political movement, and you're saying to convince people of it without even telling them what it is.
And I have no idea how you expect everyone to share the same idea of "freedom" yet be baffled by the idea of a "right". What four freedoms? Why assume they know that? What does that have to do with source code being made available?
Pretty subversive and deceptive.