Locke is a prototype of the Enlightenment thinker.  His entire premise is an Enlightenment one as he viewed the concept of government as an experiment where results could be properly predicted and assessed without temperament or bias.  He viewed government as a reciprocal relationship between those who are governed and the power they give to those who represent them.  Locke's dissection of government in this manner helped to create a view that government did not have to be an exercise in irrational and megalomaniac rule.  Rather, it can be an experiment in which individuals are able to properly assess results and data collection in the concept of government.  Additionally, I think that Locke's premise of toleration and plurality add to the scientific element of both his thought and the Enlightenment approach, in general.  For Locke, social and religious tolerance were seen as necessary absolutes, like different chemicals that can balance each other out in a chemical equation.  If all groups believed in the aims of liberal democracy and mutual respect without dominance, then the equation of political and social rule could remain balanced.  It is here where the scientific theme in Locke's thought and the Enlightenment ideas can be evident.