The ancient political theory of plato and aristotle often focused on an understanding of justice to explain politics, whereas the modern political theory of machiavelli and hobbes focuses on the concept of

On the concept of "power".

Machiavelli and Hobbes both discarded the established and medieval scholarly conventions that went before them. In particular, they dismissed the Aristotelian conviction that everything in nature, including people, has a telos or end which it yearns for. According to the theory “where there is no common power, there is no law; where no law, no injustice” 

Power

Hobbes believed that the only true and correct form of government was the absolute monarchy. This belief originated from the central idea of Hobbesian philosophy that human beings are, at their core, self-interested creatures. Machiavelli on the other hand also advocated for the use unscrupulous means for politicians in attainment of power.

A fact is a statement that is true and it can be judged objectively. So that, a fact is true and correct in all circumstances. An opinion, however, is a statement that based on a belief; it shows how someone feels. Indeed, opinion and fact are not synonyms. Both opinion and fact applied in education. Therefore, in research you can use both of them. An opinion is not always true. Therefore, it cannot be proven. It shows that the last option is not true. Opinion is not important than facts. Opinions can be based on facts. It shows that facts and opinions are not in opposition.