Reciprocity
His six persuasion techniques were...
Reciprocity
Scarcity
Authority
Consistency
Liking
Consensus
Hope this helps!
I believe the answer is: The result of legal scholars' research
Source of laws refers to the origin of binding rules that become a basis for a government to rule over its territory. To be a source of laws, the result of the researches must be tested by different variety of experts from different fields to proof its validity, so scholar's research would most likely cannot be included.
Rulers prior to the enlightenment period were seen as servants of the people. They worked hard to keep t heir kingdom's protected from harm and prosperous. As Machiavelli theorized government eventually corrupted the rulers and they became tyrants that mistreated their people. This eventually led to the common practice of revolution, such as the American Revolution. Examples would be Emperor Commodus, King Septimus Serverus, and Prince Adam of Whales.