First, Thomas Paine argued that the American colonies should free themselves from Great Britain and create their own nation.

Second, Paine supported this argument by saying that republicanism—self rule by the people—was preferable to royal and aristocratic rule from Britain, arguing that the British aristocracy was parasitical and added nothing to the good of the American people.

Third, Paine asserted that the Americans should create a republic, a government run by the people for the people, as the least intrusive form of governance. He rejected the idea of a constitutional monarchy such as the one in Great Britain, stating that any monarchy was a danger to the people. He said any monarch could potentially gain too much power and become a tyrant, so the Americans should abolish the idea of any sort of monarchial government.

These ideas are, of course, commonplace to us now, but at the time were highly radical. It was difficult for people to conceive of republican self government when they were used to the idea of monarchy and being under British rule.

The Revolutionary War (1775-1783) had already begun when Thomas Paine's fifty-page pamphlet, Common Sense, appeared in January 1776.

Common Sense was published anonymously because of its treasonous content. After its publication, the meaning and purpose of the conflict changed. Before its publication, the war was largely about unfair taxation. After the appearance of Common Sense, independence was the Americans' goal. Common Sense was a best-seller and George Washington noted its significance. Washington said,"Common Sense is working a powerful change in the minds of men."

Common Sense blamed King George III for the war. Before Common Sense, most colonists had held the British Parliament culpable for the escalating struggle. According to Paine, the Crown had abused the colonists and only independence would rectify the situation.

Several arguments for independence were put forth in the pamphlet. One argument made was that tiny England should not rule over a vast continent. Another was that a declaration of independence was necessary to secure foreign support for the war. (Foreign support, particularly that provided by France, would be instrumental in the colonists' eventual victory.) And finally, Paine called for the creation of a democratic republic.

Common Sense gave impetus to the Declaration of Independence in July 1776.

One of Thomas Paine's arguments in Common Sense was that when ordinary people help to create their government, it will produce a better system than the British one.  He gave the example of a group of people in a "sequestered part of the earth, unconnected with the rest."  Paine explained that these people would unify and then find the need to create laws to rule their land.  Their government would start out small.  As the population increased, they would have to elect citizens to represent them.  Paine suggested that elected officials must frequently meet with their electors.  He contrasted this idea with the British system.

Second, Paine expressed his thoughts that the American colonies have evolved and no longer require British rule.  He argued against the idea that the colonists should be loyal to England because it had protected the them and defended them at their own expense.  He states that they "would have defended Turkey from the same motive," which was to protect "trade and dominion."  

Third, Paine condemned the attacks of the British army on the colonists.  He drew several comparisons to a country attacking its own people, stating that "even brutes do not devour their young."  He describes England as full of tyranny.