Kepler saw it as one of the chief advantages of the Copernican system that it put order into the planetary motions. Although Copernicus had indeed noted that the planetary periods increase with their distance from the sun, he did not, as far as we know, attempt to find a relationship between the two. Believing that God would not have failed to establish some mathematically precise ratio, Kepler sought from the very first to find it. Thus we see, in some of his earliest surviving letters, his attempts to relate planetary periods to the radii of their orbits using circular quadrants intersected by straight lines. Right from the beginning, Kepler gave the sun that dynamic role that was to characterize his ‘new astronomy based upon physics’. Immediately after describing the nested polyhedra that he believed determined the number and distances of the planets, he wrote:

Next, there is a moving soul and an infinite motion in the sun, and a double decrement of motion in the movables. In the first place, there is the inequality of their circuits, caused by the unequal amplitude of the orbs, which would occur even were the moving power the same in all orbs. But (2) actually this moving power (like light, in optics) is weaker the further it is from the source.

Like it or not, a big picture of the history of science is something which we cannot avoid. Big pictures are, of course, thoroughly out of fashion at the moment; those committed to specialist research find them simplistic and insufficiently complex and nuanced, while postmodernists regard them as simply impossible. But however specialist we may be in our research, however scornful of the immaturity of grand narratives, it is not so easy to escape from dependence – acknowledged or not – on a big picture. When we define our research as part of the history of science, we implicitly invoke a big picture of that history to give identity and meaning to our specialism. When we teach the history of science, even if we do not present a big picture explicitly, our students already have a big picture of that history which they bring to our classes and into which they fit whatever we say, no matter how many complications and refinements and contradictions we put before them – unless we offer them an alternative big picture.

The production of big pictures is arguably the most significant sign of the intellectual maturity of a field. It suggests both that the field's broad contours, refined over several generations of scholarship, enjoy the approval of practitioners, and that audiences exist with an interest in or need for overviews. The situation is somewhat more complicated in the history of science, since the existence of big historical pictures precedes that of a well-defined scholarly field by about two centuries. Broadly conceived histories of science and medicine were being written in the eighteenth century, when such an all-encompassing vision was central to the claims about the progress of knowledge upon which Enlightenment ideologues set such store. The Plato to Nato style histories, characteristic of the earlier twentieth century, were written largely by isolated pioneers, and while these were used in teaching as the field was becoming professionalized, recent scholars have preferred to concentrate on a monographic style of research. Despite the existence of the series started by Wiley, and now published by Cambridge University Press, it is only in the last ten years or so that more conscious attempts have been made to generate a big-picture literature informed by new scholarship. It is noteworthy that most of this is addressed to students and general readers, although there is no logical reason why it should not tackle major theoretical issues of concern to scholars. My point about maturity still holds, then, since as a designated discipline the history of science is rather new; it is still feeling out its relationship with cognate disciplines. Big-picture histories have an important role to play in these explorations since they make findings and ideas widely available and thereby offer material through which ambitious interpretations can be debated, modified and transformed.

Among the many groups of scholars whose work now illuminates science, technology and medicine (STM), historians, it seems to me, have a key responsibility not just to elucidate change but to establish and explain variety. One of the big pictures we need is a model of the varieties of STM over time; one which does not presume the timeless existence of disciplines, or the distinctions between science, technology and medicine; a model which is both synchronic and diachronic, and both cognitive and social. To that end, this brief paper presents a historical typology of STM from about 1700 to the present by focusing on four ‘ideal’ socio-cognitive types – four knowledge structures which correspond to four sets of social relations. To some extent these are period specific, but they do not have to be – hence, one may hope, the flexibility and usefulness of the model.

This essay offers some preliminary and general considerations of big picture historiography of science, attempting an introductory specification of the topic by means of narratological analysis. It takes no strong, substantive position either pro or contra big pictures themselves, preferring an approach which is more diagnostic and heuristic in nature. After considering what may be meant by a term such as ‘big picture’ and its cognates, it interrogates the kind of desire which could lie behind the wish expressed by the conference title ‘Getting the Big Picture’: namely, that a big picture may be worth getting. It proceeds by way of a limited enquiry into what seems to be felt as a relative absence of big picture works in contemporary historiography, criticizing one very general historicocultural thesis which accounts for such an absence, advancing instead evolving features of the professional history of science community over the last thirty years as reasons for this relative absence. Concludingly, it turns the issues raised thus far on their head, in some measure at least. In trying for a more precise specification of the contemporary historiographical formation, we will discover eventually a situation not so much of relative absence of big pictures, rather one where there exists both frame and title for the picture, together with some distinguished painters' names; but where the canvas is only minimally marked, a partial and shadowy sketch, stylistically disjoined. Although this sounds paradoxical, a concrete paradox is not intended. The existence of frame and title enclosing mainly empty canvas indicates only the limitations of the pictorial metaphor for describing complex and developing sets of historiographical practice. What is instanced concludingly is less a theoretical paradox than an intelligible sequence and form of development which issues in a potential problem of practice.