If the word ‘liberty’ has any definite sense attached to it, and if it is consistently used in this sense, it is almost impossible to make any true general assertion whatever about it, and quite impossible to regard it either as a good thing or a bad one. If, on the other hand, the word is used merely in a general popular way without attaching any distinct signification to it, it is easy to make almost any general assertion you please about it; but these assertions will be incapable of either proof or disproof as they will have no definite meaning. Thus the word is either a misleading appeal to passion, or else it embodies or rather hints at an exceedingly complicated assertion, the truth of which can be proved only by elaborate historical investigations.

James Fitzjames Stephen, Liberty, Equality, Fraternity, London, 1873, p. 184