湖の彼岸　－向こう岸の街、水面に映った社会、二重写しの自分－

British gentleman, political activist, legal scholar, social philosopher, linguist, Jeremy Bentham is best known as the founder of British "utilitarianism" or "philosophical radicalism".

Born into a wealthy Tory family, Jeremy Bentham was educated at Westminster school and Queen's College, Oxford. He trained as a lawyer and was called to the bar in 1769. His independent wealth permitted him to set himself up as a writer in London. According to his contemporary William Hazlitt, "Bentham has lived for the last forty years in a house in Westminster...like an anchorite in a cell, reducing law to a system, and the mind of man to a machine."

In 1768 that Bentham came across a political tract by Joseph Priestley in which the the phrase "the greatest happiness for the greatest number" was invoked. Intrigued, Bentham followed this up by reading Hume, Helvetius and Beccaria and slowly began forming his utilitarian ideas.

Bentham's first book (1776) was an attack on Blackstone's immensely popular Commentaries on the Laws of England. For Bentham, Blackstone's obsession with the "rule of law" made a fetish out of ancient laws that were long outdated and prevented the passing of new legislation more appropriate for changing circumstances. Bentham claimed that all laws, ancient and modern, should be evaluated according to the single ethical principle of "utility". A law is good or bad depending upon whether or not it increased general happiness of the population.

From 1785 to 1788, Bentham traveled to Russia to visit his brother. Upon his return, he published his most famous work, Introduction to the Principles of Morals (1789), which has been widely regarded as the founding document of British utilitarianism. In 1791-94, Bentham actively campaigned for his "model prison" -- the "Panopticon". Bentham's first disciple, ノtienne Dumont, published French translations of several of Bentham's works, giving him a good deal of popularity abroad. Despite his adamant opposition to the "natural law" language and principles of the 1776 Declaration of Independence and the 1789 Declaration of the Rights of Man, Bentham welcomed both the American and French Revolutions. He was made an honorary citizen of the French Republic in 1792.

expounding tract after tract on utilitarian philosophy, legal theory and social reform. He struck up important friendships with the politicians Earl of Shelburne and William Pitt and the economist David Ricardo.

His first book (1776)

Bentham introduced the distinction between individual "hedonic calculation" (maximizing individual utility) as a basis of a positive theory of behavior, and social calculation (maximizing aggregate utility) as a normative theory of social organization.

"Nature has placed mankind under the governance of two sovereign masters, pain and pleasure. It is for them alone to point out what we ought to do as well as to determine what we shall do. On the one hand, the standard of right and wrong, on the other the chain of causes and effects, are fastened to their throne." (Bentham, 1780).

Bentham argued that virtually all humans seek to maximize their "happiness", defined as the surplus of pleasures over pains. He also posited that all human actions arise from the hedonic calculus. Altruism, asceticism, love, duty, a desire for freedom, obedience to the law, faith, etc. are reducible to individual pleasure and pain calculations. By applying his utility hypothesis so widely, Bentham made it empirically unverifiable. No piece of evidence could conceivably be brought up to disprove it.

Bentham also correlated happiness with the means to happiness. The wealthier a person is, the greater the happiness he can attain. However, he recognized the principle of diminishing marginal utility, i.e. that the greater the amount of utility a person already has, the smaller will be the utility gain of any extra increment of wealth.

The critical question Bentham puzzled over was whether the unhindered pursuit of individual happiness could be reconciled with morality. The only ethical principle he accepted was that increasing general happiness is "good", while decreasing it is "bad". From the outset, then, Bentham dismissed all "ipsedixitisms", i.e. moral judgments based on criteria such as "sympathy" or "intentions". Similarly, all abstract notions of social ethics like "natural rights", "social justice", etc. were hogwash. For Bentham, only consequences mattered. Actions are to be judged strictly on the basis of how their outcomes affect general utility.

But what is general utility of a society? Bentham argued it was no more and no less than the sum total of individual utilities of all members of a society. Whom we include in our definition of "society" depends on our sphere of consideration. It may be a nation, it may be all of humanity. It may be confined to living adult voters, or it may embrace all people and generations yet unborn.

What is utility?

He emphasized the need for equal weights in this summation: no person's utility counted more than another's (it somehow slipped Bentham's notice that this presumption implicitly introduces elements of some "natural law" doctrines, but so be it).


of "equal capacity for pleasure" was a natural law notion slipped through.

Insisting that individuals are the best judges of their own happiness, Bentham had an automatic tendency to default to non-interference by government. However, he recognized that individual actions of one individual often implicated the happiness of others and that individuals may not have the incentive or ability to coordinate concerted actions that improve aggregate utility.

As such, Bentham laid some responsibilities in the hands of the State. The first obligation is to not let people suffer needlessly. This means guaranteeing a minimal subsistence level of income to ensure survival for all citizens and the provision of security of individuals (as well as their property) against the violence of other citizens or foreign nations.

The second obligation is to encourage abundance, both of wealth and of population. This was a tricky issue. If wealth is constant, then a greater population will reduce wealth per capita. However, Bentham believed that a plentiful population is necessary for defense. At any rate, as argued by Paley (1785), by the principle of diminishing marginal utility and direct summation of utility, a large but poor population might have a higher "aggregate utility" than a small and rich population.

The third obligation was equality of means. By the principle of diminishing marginal utility, an extra 」1 contributes less utility to a rich man than it does to a poor one. Consequently, reallocation of income to complete equality is desirable as the utility loss of the rich is more than compensated by the utility gain of the poor. However, he recognized that radical redistribution can also thwart incentives and productivity, and thus decrease general abundance. Bentham argued that some amount of redistributive taxation is warranted, but it must be carefully balanced against these other considerations. He thought that progressive inheritance taxes, as they have few adverse effects on incentives, were the best solution.

Mill (1850) implicitly defined the ideal population as that which maximized average happiness per head (a definition later attributed to Cannan). Sidgwick (1894) defined maximum happiness = average happiness x population, a solution greatly applauded by Edgeworth (1877, 1881).


as enshrined in Blackstone's Commentaries and political documents such as the 1776 American Declaration of Independence and the 1789 French Declaration of the Rights of Man.

dismissed all "ipsedixitisms", i.e. moral judgments based on criteria such as "sympathy" or "intentions". For Bentham, only consequences mattered. Actions are to be judged strictly on the basis of how their outcomes affect general utility.

Social utility was a bit more complicated. He invoked Helvetius's phrase, "greatest happiness for the greatest number" as his general ethical principle. Bentham dismissed all notions of "natural rights" or "social contracts" as enshrined in Blackstone's Commentaries and political documents such as the 1776 American Declaration of Independence and the 1789 French Declaration of the Rights of Man. He also dismissed all "ipsedixitisms", i.e. moral judgments based on criteria such as "sympathy" or "intentions". For Bentham, only consequences mattered. Actions are to be judged strictly on the basis of how their outcomes affect general utility.


If the objective is to maximize light in a room, it might be better to use one strong lamp rather than five weak candles.



経済思想の歴史
http://cruel.org/econthought/profiles/bentham.html