Freedom is part of the inherited Old English vocabulary. It is a derivative of free, and many of its most important uses are in compounds, collocations, phrases, and constructions determined by its relationship with this adjective. From its earliest history it has defined the rights and privileges of a free individual, and the state of having such rights and privileges, in early use especially in contrast with slavery or serfdom, but increasingly seen as liberty from despotic or autocratic control.

Liberty is a borrowing from French and in turn from Latin, and is first found in the late fourteenth century. As a simplex word its core meanings overlap almost completely with those of freedom. Both words are used to denote both ‘freedom to act’, and ‘freedom from despotism’. This broad synonymy has held true from the early modern English period onwards.

Both words have countable uses, although in the case of liberty these are usually more restricted semantically; compare e.g. “hard-won freedoms” with “to take liberties”. Special countable uses of liberty also occur in legal usage, as e.g. with reference to a liberty granted by a sovereign.

In non-countable uses the two words overlap very considerably, although freedom is more frequent with reference to specific actions performed without restraint, as in “freedom of speech”, “the freedom of his remarks”, “freedom of movement”, “the freedom of his brush strokes”; many such uses are clearly nominalizations of expressions with the adjective free, especially free speech. Similarly free from is the model for freedom from (persecution, harm, taxes, etc.).

In some cases questions of alliteration and/or prosody have clearly shaped choices. Hence liberation struggles are typically conducted by freedom fighters, probably on account of alliteration and prosody; hence also such collocations as the fight for freedom, those who are fighting for freedom, etc.

The relative frequency of the two words has shifted dramatically. In 16c and 17c, in spite of being a relatively recent borrowing, liberty outnumbers freedom by approximately four to one; in 18c it continues to be more frequent, but by rather less than two to one. In 19c British newspapers liberty remains approximately twice as frequent as freedom; in nineteenth-century US sources liberty only very slightly outnumbers freedom, if at all. This is in contrast to late 20c and early 21c sources, in which freedom is typically about three times more frequent than liberty, in both British and U.S. sources. This seems to hold true both for newspapers and for corpora representing a wide range of different genres. Corpus searches indicate no extremely frequent collocations or compound uses which alone can account for this shift (although e.g. academic freedom, religious freedom, individual freedom, press freedom, freedom fighter, freedom of speech, freedom of expression are all very common, as is civil liberty).

During the course of its history liberty shows a complex set of relationships with a number of other words ultimately from the same derivational group, which characteristically have connections with aspects of radical politics in their early use. An interesting question is whether any of these associations have contributed to the decreasing frequency of liberty relative to freedom.

From the early modern period libertine (with its derivatives libertinism and libertinage) is found in English as a borrowing from French and Latin, ultimately showing, like liberty, a derivative formation from Latin liber ‘free’. As both noun and adjective the word has important early uses denoting a ‘free-thinker’, especially in religion, although in later use lack of restraint in moral life, especially with regard to sexual morality, becomes the dominant meaning. In early use the relationship between the terms liberty and libertinism is an ambiguous one: sometimes liberty is identified as the aim of libertines, sometimes liberty is the ideal condition to be protected from the excesses of libertinism; the latter seems to become more dominant over time.

The positive connotations of liberty in 18c are reflected by the frequency of defence of liberty, which is found only sparingly in the early modern period (when defence of freedom is found hardly at all). Defence of liberty continues to be more common than defence of freedom in 19c, although again the situation is reversed in contemporary usage. The range of conflicts in which both phrases have been employed for propaganda purposes is huge. In 20c the Cold War collocation the Free World (now frequently, albeit most often tacitly, redefined in the context of the “War on Terror”) may be a factor favouring defence of freedom, although this must be seen in the context of the general increase in frequency of freedom relative to liberty over time. The recent past has additionally seen for example Operation Iraqi Freedom and Operation Enduring Freedom in Afghanistan.

In late 18c we find a very strong association of liberty’s French equivalent liberté with the Revolutionary motto liberté, égalité, fraternité, and we also find that liberty has a prominent use in the US Declaration of Independence (“Life, Liberty and the pursuit of Happiness”) and the U.S. Constitution. In 19c (and later) Anglophone discourse freedom has at least the capacity for uses dissociated from the radical associations of liberty. Arguably these are realized for instance in the tradition of nationalistic accounts of early English history, in which the freedom of the Anglo-Saxon churl is stressed as an inherited fundamental aspect of English society stretching back into the mists of an early Germanic inheritance (following an analysis abandoned by more recent historians).

In the nineteenth century both liberalism and libertarianism take on political meanings starkly opposed to conservatism, although a ‘liberal’ position is also eschewed by many on the more radical left. As Williams notes, association with the broader use of the word liberal, and hence connotations of ‘wishy-washiness’ or excessive generosity, probably have a part to play here. The derivational relationship is clearest and strongest in the case of libertarianism, although this is also the term which has achieved much less extensive general currency.

In the mid 20c liberty shows a further derivational relationship with liberation, which shows uses in post-colonialism, theology, and women’s and gay liberation. However, as noted, those engaged in such liberation struggles are typically freedom fighters.

It is possible that close stylistic and linguistic analysis of the use of either liberty or freedom (or, as frequently today, liberty and freedom) may yield interesting insights into the influences and sympathies of particular individuals or groups. Such analyses are becoming much more practicable in the digital age, and may prove valuable for linguists, lexicographers, and social historians.

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抄录如下：

小议Liberty & freedom