The inalienable right to life was famously enshrined by Thomas Jefferson in the Declaration of Independence. The basis for this claim was made by John Locke, who argued that in a state of nature, all individuals would be naturally disposed towards securing their own survival. Difficulties arising from the enforcement of this right by individuals (such as the tendency towards cycles of revenge) are one of the reasons Locke gave for the inception of the social contract through consent of the governed.
The right to property is a natural right, in the views of 18th century philosophers, because the human body is that which is most fundamentally one's own. This domain of influence naturally extends to a certain perimeter, within which individuals are free to use any available means to maximize and improve their quality of life. According to Rousseau, the defense of property is one of the reasons why individuals move beyond the state of nature, surrendering some private interests for the benefits of cooperation.
Rousseau argued that the right to liberty was a natural right, meaning that slavery is contrary to nature. He argued that slavery could not be legitimated either as the result of conquest or through coerced surrender of one's freedom. Further, the fact that all individuals are entitled to liberty forces the conclusion that a tyrannical government which usurps individual rights may be overturned through revolution.
The German philosopher Georg Friedrich Hegel argued that the right to conscience, moral and religious freedom was inalienable because it was this freedom which differentiated a person from a mere object. He said that this faculty is that which can only belong to the individual and can never be passed to anyone else or annulled by any act of despotism.