The following is an example of reasoning from principle: "All infringements on the right of free expression are unconstitutional. Limitations on the lyrics of popular songs are infringements on the right of free expression. Therefore, all limitations on the lyrics of popular songs are unconstitutional."

This is a true sentence

Explanation:

"All infringements on the right of free expression are unconstitutional. Limitations on the lyrics of popular songs are infringements on the right of free expression. Therefore, all limitations on the lyrics of popular songs are unconstitutional."

Reasoning from principle follows two premises that are the non-contradiction and that all reasoning begins with premises and ends with conclusions, This examples present the premises about all the things that are considered unconstitutional, and adds one specific example that violates that rule, then we have the conclusion and the three stages don't contradict themselves in any way.