This article traces disagreements about the genetic effects of low-dose radiation exposure as waged by James Neel, a central figure in radiation studies of Japanese populations after World War II, and Yuri Dubrova, who analyzed the 1986 Chernobyl nuclear power plant accident. In a 1996 article in Nature, Dubrova reported a statistically significant increase in the minisatellite DNA mutation rate in the children of parents who received a high dose of radiation from the Chernobyl accident, contradicting studies that found (...) no significant inherited genetic effects among offspring of Japanese A-bomb survivors. Neel’s subsequent defense of his large-scale longitudinal studies of the genetic effects of ionizing radiation consolidated current scientific understandings of low-dose ionizing radiation. The article seeks to explain how the Hiroshima/nagasaki data remain hegemonic in radiation studies, contextualizing the debate with attention to the perceived inferiority of Soviet genetic science during the Cold War. (shrink)
Material objects persist through time and survive change. How do they manage to do so? What are the underlying facts of persistence? Do objects persist by being "wholly present" at all moments of time at which they exist? Or do they persist by having distinct "temporal segments" confined to the corresponding times? Are objects three-dimensional entities extended in space, but not in time? Or are they four-dimensional spacetime "worms"? These are matters of intense debate, which is now driven by concerns (...) about two major issues in fundamental ontology: parthood and location. It is in this context that broadly empirical considerations are increasingly brought to bear on the debate about persistence. Persistence and Spacetime pursues this empirically based approach to the questions. Yuri Balashov begins by setting out major rival views of persistence -- endurance, perdurance, and exdurance -- in a spacetime framework and proceeds to investigate the implications of Einstein's theory of relativity for the debate about persistence. His overall conclusion -- that relativistic considerations favour four-dimensionalism over three-dimensionalism -- is hardly surprising. It is, however, anything but trivial. Contrary to a common misconception, there is no straightforward argument from relativity to four-dimensionalism. The issues involved are complex, and the debate is closely entangled with a number of other philosophical disputes, including those about the nature and ontology of time, parts and wholes, material constitution, causation and properties, and vagueness. (shrink)
Yuri Balashov sets out major rival views of persistence--endurance, perdurance, and exdurance--in a spacetime framework and proceeds to investigate the implications of Einstein's theory of relativity for the debate about persistence. His overall conclusion--that relativistic considerations favour four-dimensionalism over three-dimensionalism--is hardly surprising. It is, however, anything but trivial. Contrary to a common misconception, there is no straightforward argument from relativity to four-dimensionalism. The issues involved are complex, and the debate is closely entangled with a number of other philosophical disputes, (...) including those about the nature and ontology of time, parts and wholes, material constitution, causation and properties, and vagueness. (shrink)
Background and assumptions. Persistence and philosophy of time ; Atomism and composition ; Scope ; Some matters of methodology -- Persistence, location, and multilocation in spacetime. Endurance, perdurance, exdurance : some pictures ; More pictures ; Temporal modification and the "problem of temporary intrinsics" ; Persistence, location and multilocation in generic spacetime ; An alternative classification -- Classical and relativistic spacetime. Newtonian spacetime ; Neo-Newtonian (Galilean) spacetime ; Reference frames and coordinate systems ; Galilean transformations in spacetime ; Special relativistic (...) spacetime ; Length contraction and time dilation ; Invariant properties of special relativistic spacetime -- Persisting objects in classical spacetime. Enduring, perduring, and exduring objects in Galilean spacetime ; The argument from vagueness ; From minimal D-fusions to temporal parts ; Motivating a sharp cutoff ; Some objections and replies ; Implications -- Persisting objects in Minkowski spacetime. Enduring, perduring, and exduring objects in Minkowski spacetime ; Flat and curved achronal regions in Minkowski spacetime ; Early reflections on persisting objects in Minkowski spacetime : Quine and Smart ; "Profligate ontology"? ; Is achronal universalism tenable in Minkowski spacetime? ; "Crisscrossing" and immanent causation -- Coexistence in spacetime. The notion of coexistence ; Desiderata ; Coexistence in Galilean spacetime ; Coexistence in Minkowski spacetime : CASH ; Alexandrov-Stein present and Alexandrov-Stein coexistence ; AS-Coexistence v. CASH : symmetry, multigrade, and objectivity ; As-coexistence v. CASH : relevance ; The mixed past of coexistence ; No need in the extended now -- Strange coexistence? Coexistence and existence@ ; The asymmetry thesis ; The absurdity thesis ; Collective CASH value of coexistence ; Collective existence@ and coexistence in classical spacetime ; Collective existence@ and coexistence in Minkowski spacetime ; Contextuality ; Chronological incoherence ; Some objections -- Shapes and other arrangements in Minkowski spacetime. How rigid is a granite block? ; Perspectives in space ; Perspectives in spacetime ; Are shapes intrinsic to objects? ; The causal objection ; The micro-reductive objection ; Pegs, boards, and shapes ; Perduring objects exist. (shrink)
In this paper I develop three different arguments against the thesis that knowledge-how is a kind of knowledge-that. Knowledge-that is widely thought to be subject to an anti-luck condition, a justified or warranted belief condition, and a belief condition, respectively. The arguments I give suggest that if either of these standard assumptions is correct then knowledge-how is not a kind of knowledge-that. In closing I identify a possible alternative to the standard Rylean and intellectualist accounts of knowledge-how. This alternative view (...) illustrates that even if the arguments given here succeed it might still be reasonable to hold that knowing how to do something is a matter of standing in an intentional relation to a proposition other than the knowledge-that relation. (shrink)
How should intellectualists respond to apparent Gettier-style counterexamples? Stanley offers an orthodox response which rejects the claim that the subjects in such scenarios possess knowledge-how. I argue that intellectualists should embrace a revisionary response according to which knowledge-how is a distinctively practical species of knowledge-that that is compatible with Gettier-style luck.