John Locke is known the father of Liberal Democracy, basis of western constitutional democracy
. He was from a puritan family and he lived during the time of Hobbes. He believed that Men being, as has been said, by nature, all free, equal, and independent, no one can be put out of this state, and subjected to the political power of another, without his own consent. the only way whereby anyone divests himself of his natural liberty, and puts on the bonds of civil society, is by agreeing with other men to join and unite into a community for their comfortable, safe , and peaceable living one amongst another, in a secure enjoyment of their properties, and a greater security against any, that are not of it.

Locke liked Descartes’ method of clearing the slate to find out how people got to know things. But human reason wasn’t the answer that Locke came up with. He said that all knowledge begins with what comes to the mind through the senses. Only then can people begin to organize this information through reason. He said that no -one knows anything at birth. “The mind is a blank piece of paper.”

Locke became interested in medicine at Oxford University. He studied medicine part-time and became well qualified. He also rubbed shoulders with lots of famous people. He was a lecturer at Oxford university and his friend Isaac Newton discovered gravity. The most powerful was lord Shaftesbury, who made Locke his personal secretary and doctor. When an abscessed liver threatened to kill Shaftesbury, Locke operated on the his diseased liver and fitted it with a silver tap.
Shaftesbury rose to Lord Chancellor, and he made Locke a government minister. But Shaftesbury’s intrigues get them both into trouble with CHarles II, the newly reinstated king. Locke was a careful man, however. He wrote his notes in code and crossed out names and places. He even used invisible ink with which he wrote romantic letters to his many lady friends, though he never married. The king’s spies reported that Locke lived “very cunning and unintelligible life”.

John Locke’s idea of Monarchy:

Locke argued that paternal power is not the same as political power. Paternal power legitimate for those subjects who are not capable of reasoning – like children. For reasoning adults, power comes from consent. And consent is always limited. Rational adults would never consent to, or contract for, an absolute power over them.
Locke’s definition of the “State of nature”:

Locke’s definition of the “State of war”:

Difference between the State of Nature and the State of War:
Men living together according to reason without a common superior on earth, with authority to judge between them, is properly the State of Nature. But force or a declared design of force upon the person of another, where there is no common superior on earth to appeal to for relief, is the state of war; and it is the want of such an appeal gives a man the right of war even against an aggressor, though he be in society and a fellow-subject. A state of war is much much more likely to occur in a political society in which the concentrated power of government is easily abused than in the state of nature in which power dispersed among many individuals.
A state of war exists when there is “force without right upon a Man’s person”. But in a state of nature people follow reason and natural law. We are naturally reasonable creatures. This rational capacity is Natural Law. This Rational capacity always allows us to rise above our self-interest. We hand over the right or power of executing the laws of nature which in the state of nature we carried out ourselves. for instance, the right to punish those who have harmed us.
Some other Locke’s beliefs in brief:

Sovereignty is located not with the government but with the people. the social contract create sovereignty, not the political contract. We require a Social Contract to take us beyond the state of nature.
Justification of Revolution: If the government should violate its trust by using illegitimate force, it is in violation of the social contract, and the people have the right to revolt. Revolution is not caused by a peoples violent disposition. The people are essentially conservative. Revolution is brought about by the governments violation of the people’s trust. It is the social, not the political contract which provides order and peace.
Property: Though the earth, and all inferior creatures, be common to all men, yet every man has a property in his own person; this no body has any right to but himself. The labour of his body, and the work of his hands, we may say, are properly his. For this labour being the unquestionable property of the labourer, no man but he can have a right to what that is once joined to, at least where there is enough, and as good, left in common for others. Everyone owns themselves – and their labour. When human beings add their labour to Nature, they transform it to private property.