* Natural rights: Locke believed that all people are born with certain unalienable rights, including life, liberty, and property. These rights are not granted by the government but are inherent in our nature.
* Limited government: Locke argued that the government's only legitimate role is to protect our natural rights. The government should not interfere with our personal lives or our property.
* Separation of powers: Locke believed that the powers of government should be divided among different branches to prevent any one branch from becoming too powerful.
Montesquieu
* Separation of powers: Montesquieu agreed with Locke that the powers of government should be divided among different branches. He also believed that the judiciary should be independent of the other branches of government.
* Checks and balances: Montesquieu argued that each branch of government should have the ability to check the power of the other branches. This system of checks and balances helps prevent any one branch from becoming too powerful.
Rousseau
* Social contract: Rousseau believed that the government is a contract between the people and the ruler. The ruler agrees to protect the people's natural rights, and the people agree to obey the ruler's laws.
* Popular sovereignty: Rousseau argued that the people are the ultimate source of political power. The government is only legitimate if it is based on the consent of the governed.
Voltaire
* Freedom of speech: Voltaire believed that freedom of speech is essential for a free and democratic society. He argued that people should be able to express their opinions without fear of reprisal.
* Religious toleration: Voltaire also believed in religious toleration. He argued that people should be free to practice their religion without fear of persecution.
Beccaria
* Penal reform: Beccaria argued for the reform of the criminal justice system. He believed that the punishment for crime should be proportional to the crime, and that the goal of punishment should be rehabilitation, not revenge.
The ideas of these philosophers had a profound influence on the Founding Fathers. They helped shape the principles of the American Revolution and the U.S. Constitution. These ideas continue to influence American politics and law today.