Excerpted from “Jeremy Bentham,” in The Internet Encyclopedia of Philosophy,
http://www.iep.utm.edu/bentham/

Bentham was regarded as the central figure of a group of intellectuals called, by Elie Halévy, "the philosophic radicals"; both J. S. Mill and Herbert Spencer can be counted among the 'spiritual descendants' of this group. While it would be too strong to claim that the ideas of the philosophic radicals reflected a common political theory, it is nevertheless correct to say that they agreed that many of the social problems of late eighteenth and early nineteenth century England were due to an antiquated legal system and to the control of the economy by a hereditary landed gentry opposed to modern capitalist institutions. As discussed in the preceding section, for Bentham, the principles that govern morals also govern politics and law, and political reform requires a clear understanding of human nature. While he develops a number of principles already present in Anglo-Saxon political philosophy, he breaks with that tradition in significant ways.

In his earliest work, A Fragment on Government (1776) (an excerpt from a longer work published only in 1928 as Comment on Blackstone's Commentaries), Bentham attacked the legal theory of Sir William Blackstone. Bentham's target was, primarily, Blackstone's defense of tradition in law. Bentham advocated the rational revision of the legal system, a restructuring of the process of determining responsibility and of punishment, and a more extensive freedom of contract. This, he believed, would favor not only the development of the community, but the personal development of the individual.

Bentham's attack on Blackstone targeted more than the latter's use of tradition however. Against Blackstone and a number of earlier thinkers (including Locke), Bentham repudiated many of the concepts underlying their political philosophies, such as natural right, state of nature, and 'social contract.' Bentham then attempted to outline positive alternatives to the preceding 'traditionalisms.' Not only did he work to reform and restructure existing institutions, but he promoted broader suffrage and self (i.e., representative) government.

From “A Fragment on Government” (1776) –
“It is the greatest happiness of the greatest number that is the measure of right and wrong.”

From “Anarchical Fallacies” (1816; English trans. 1843) –
“Natural rights is simple nonsense: natural and imprescriptible rights, rhetorical nonsense, -- nonsense upon stilts.”