In april 1872, with the caisson at a depth of seventy-odd feet and still no bedrock, two men died. The strain for Roebling was nearly unbearable, as his wife later said. On May 18, a third man died, and that same day Roebling made the most difficult and courageous decision of the project. Staking everything — the success of the bridge, his reputation, his career - he ordered a halt. The New York tower, he had concluded, could stand where it (...) was, at a depth of 78 feet 6 inches, not on bedrock, but on “hardpack” sand. From examinations of the strata he had determined to his own satisfaction that no movement had occured at the level since the time of deposit millions of years in the geologic past; so, he said, it was “good enough to found upon”. (shrink)

In response to a recent argument by David Bloor, I argue that denying absolutes does not necessarily lead to relativism, that one can be a fallibilist without being a relativist. At issue are the empirical natural sciences and what might be called “framework relativism”, that is, the idea that there is always a conceptual scheme or set of practices in use, and all observations are theory-laden relative to the framework. My strategy is to look at the elements that define a (...) relativist stance and show where the pragmatic fallibilist disagrees. Defending the pragmatic notion of experience will be central, given that relativists reject the idea that experience can play a role in objectively justifying belief. We can reject all absolutes and start from the premise that everything is historical, contingent, and situated. One of the lessons of pragmatism is that universal and fixed principles are not necessary for objective knowledge. (shrink)

Within the philosophy of science there has been a great deal of rather vague talk about the 'heuristic fruitfulness' (or what Peirce called the 'esperable uberty') of theories. It is my aim in the present paper to add some precision to these discussions by linking this 'fruitfulness' to the satisfaction of certain heuristic criteria. In this manner the demarcation between 'discovery' and 'pursuit' becomes blurred. As a case study, I present the competition between the paraparticle and colour models of quarks (...) in the late 1960s. I argue that the eventual appraisal of the latter as the more fruitful of the two was based on the incorporation of a particular symmetry principle, regarded as a heuristic guideline, rather than on non-epistemic factors concerning 'cognitive resources' and the like. (shrink)

In this chapter I investigate the prospects of integrated history and philosophy of science, by examining how philosophical issues raised by “hidden entities”, entities that are not accessible to unmediated observation, can enrich the historical investigation of their careers. Conversely, I suggest that the history of those entities has important lessons to teach to the philosophy of science. Hidden entities have played a crucial role in the development of the natural sciences. Despite their centrality to past scientific practice, however, several (...) of them (e.g., phlogiston, caloric, and the ether) turned out to be fictitious. For this reason, they have figured prominently in recent debates on scientific realism. The issues I explore in this paper are entangled with those debates. I argue that our understanding of hidden entities and their role in experimental practice can be enhanced by adopting an integrated historical-cum-philosophical approach. On the one hand, philosophical reflection on the reality of those entities has a lot to gain by examining historically how they were ntroduced and investigated. On the other hand, the historical reconstruction of the careers of those entities may profit from philosophical reflection on their existence. (shrink)