Here's a breakdown:
* Own experiences and observations: Machiavelli served in various positions in the Florentine Republic, including as a diplomat and a secretary of the Ten of War. This gave him firsthand experience with the intricacies of politics, the workings of government, and the nature of power. He witnessed firsthand the rise and fall of political figures and the machinations of ambitious rulers.
* Historical examples: Machiavelli drew heavily on historical examples, both ancient and contemporary. He studied the works of ancient historians like Livy and Plutarch, and he also analyzed the rise and fall of Italian city-states, as well as the political landscape of his own time.
* Contemporary political thought: Machiavelli was influenced by contemporary political thinkers such as Leonardo Bruni, who advocated for a more secular and civic-minded approach to politics, and Francesco Guicciardini, who provided a more pragmatic and less idealistic view of power.
It's important to note that "The Prince" is not a scholarly work in the traditional sense. It's more of a practical guide for rulers, offering advice based on Machiavelli's own observations and understanding of human nature. He didn't rely on any particular academic discipline or theoretical framework.
Instead, he combined his own experiences, historical examples, and contemporary thought to create a unique work that has been both praised and criticized for its realism and its amoral perspective on power.