The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.

Kantorowicz's exposition of Bracton's conception of kingship has reopened an old question, the meaning of the passage in which Bracton deals with the statement, “quod principi placuit legis habet vigorem.” It reads:

Nihil enim aliud potest rex in terris, cum sit dei minister et vicarius, nisi id solum quod de iure potest, nec obstat quod dicitur quod principi placet legis habet vigorem, quia sequitur in fine legis cum lege regia quae de imperio eius lata est, id est non quidquid de voluntate regis temere praesumptum est, sed quod magnatum suorum consilio, rege auctoritatem praestante et habita super hoc deliberatione et tractatu, recte fuerit definitum.

Perhaps no important publicist has baffled interpretation more persistently than Marsiglio of Padua. His originality compels recognition; but it seems difficult to determine in what it consisted. Claims that he anticipated modern equalitarian democracy, separation of powers, or separation of church and state have each evaporated on closer inspection. Recently it has been claimed that he made a revolutionary breach with mediaeval tradition in his concept of law: rejecting previous attempts to define law in substantive terms, he first presented a purely positivist theory.

That there was a continuity between medieval political thought and the body of systematic theory that surrounded the Declaration of Independence and the Constitution is by now a commonplace. But when we speak of the medieval contribution to the American political tradition, it is important to avoid the implication that what medieval thought contributed was identical with what American thought received. Between the close of the fifteenth century and the latter part of the eighteenth lie some two and a half centuries of crowded thought and experience, which more or less profoundly changed the meaning of concepts continuously in use. The more we learn of medieval theory, the clearer it becomes that it must be interpreted in its own terms rather than in terms of its derivatives. And the American political tradition, of course, cannot be fully understood in terms of its historic roots. Perhaps the chief service which the history of ideas can offer to political theory lies in providing material for the sharpening of concepts through a comparative analysis. For the full understanding of the meaning of an idea, one needs to know not only what it is, but also, I suggest, what it is not. Thus there may be value in an attempt to define the medieval meaning of some concepts that were a significant part of the medieval contribution: in particular, sovereignty, natural law and natural rights, and consent.

The purpose of this paper is a re-examination of the thesis set forth by Otto von Gierke: that in medieval political theory there were certain organic tendencies which, because the jurists failed to develop the concept of the real personality of the group, ultimately gave way to an atomistic construction of the state. The paper is not concerned with the actual structure of medieval society, nor with the legal concepts of jurists, but with the theoretical doctrines of the publicists which Gierke interprets in that section of Das deutsche Genossenschaftsrecht which, in Maitland's translation, has become a classic for students of political theory. It is my contention that, while his treatment of subordinate issues of medieval political theory is often masterly, Gierke's main theses in regard to the medieval concepts of the nature of the group, the relation of officers to the group, and the relation of groups to one another are fundamentally inaccurate.