Schaffer on Herschel’s Cosmology

In thinking about why I enjoy working in the history of science so much, the answer I increasingly come up with is that it gives us a sort of understanding of why arguments are structured in the way that they are, and, crucially, why they make sense to those who make them. Others seem to like to study science as a repository of accepted knowledge, or as a tool for technological development or for structuring society, or simply as a subset of museological reconstruction. But, in my mind, work like, say, Peter Dear’s, which regularly traces not just the connection between scientific work and its time and place, but the reason why arguments make sense in different times and places, is the most exciting. Looking at science in this vein, it is possible to see it as more than just “knowledge functioning in society” but as a social institution dedicated to the construction of highly sophisticated methods of arriving at “knowledge one can rely on”.

So, what does an article about theories of things like sunspots being holes in the solar atmosphere leading down to a temperate layer where intelligent beings live have to do with “knowledge one can rely on”? As I explored a little bit in my prior post on “cosmology and the problem of the problem”, the ability to connect knowledge into a coherent world system has long been a crucial method of argumentation. It is misleading to look at the scientific revolution and assume one of its major products was an argumentative restraint that refused to intuit knowledge where no reliable knowledge could be found (case-in-point, Newton’s celebrated “hypotheses non fingo”). This is because, first, speculation is always necessary to the development of new knowledge, and, second, it is incredibly problematic to determine when one does or does not have the knowledge available to formulate useful hypotheses concerning problematic phenomena. Who could blame people for trying to figure out how the sun burned before nuclear fusion was understood, and what suddenly gave physicists permission to use fusion as an explanation once they did?

Simon Schaffer’s very fun piece, “‘The Great Laboratories of the Universe’: William Herschel on Matter Theory and Planetary Life,” (Journal of the History of Astronomy, 1980), discusses William Herschel’s struggle to reconcile various pieces of knowledge into a coherent cosmology. Specifically, Newton’s theory of gravity caused enormous problems for explaining things like star clusters and nebulae, which, by contemporary understanding, should collapse in on themselves if gravity were indeed the only “central power” at play; similarly, Newton’s particulate theory of light raised serious questions about why the sun’s mass doesn’t diminish with time.

Without going into the whole evolution of Herschel’s elaborate cosmology (the curious will have to track down the article), following longstanding natural philosophical traditions, he sought to find answers to these problems by suggesting consistent explanations for why the universe appeared the way it did, drawing on contemporary theories of matter and forces. In addition to gravity, these included chemical forces and fermentation (which wasn’t then considered connected to biological processes), as well as material things like luminous and translucent fluids that were widely supposed to exist, especially beyond the earth. Assembling these known or supposed pieces of knowledge into an “economy of the heavens” in which comets did things like replenish the sun’s diminished luminous fluid and in which nebulae collapsed to become stars (that could and probably did support life), Herschel created an intellectually stable universe.

Crucially, Schaffer’s piece is not a reliquary of later-rejected scientific ideas, nor is it merely a demonstration of the links between Herschel’s ideas, and, say, the religious principles and gentlemanly culture of his day. It is a tour of a specific cosmology that, in turn, serves as a means of understanding why natural philosophical cosmologies had epistemological impetus. Specifically, it shows the importance of self-consistency of argument and consistency with known observations, and thus, the circumvention of objections as powerful argumentative devices. There’s still historical work like this out there, but I’d love to see it have a more central place in the profession.

It’s also worth pausing to think about what strategies we are using and will use to explain new counter-intuitive observations like the accelerating universe, and what argumentative similarities they will have to Herschel’s construction of a unified cosmology in terms of “understood” forces and forms of matter. His conclusions may have been strange to us, but were his argumentative methods really so weird as one might imagine?

In our next installment of this series, we’ll look at natural philosophy in a more generalized study with Schaffer’s 1983 “Natural Philosophy and Public Spectacle in the Eighteenth Century”.