Popper’s (1983, 2002) philosophy of science has enjoyed something of a renaissance in the wake of the replication crisis, offering a philosophical basis for the ensuing science reform movement. However, adherence to Popper’s approach may also be at least partly responsible for the sense of “crisis” that has developed following multiple unexpected replication failures. In this article, I contrast Popper’s approach with that of Lakatos (1978) as well as with a related but problematic approach called naïve methodological falsificationism (NMF; Lakatos, (...) 1978). The Popperian approach is powerful because it is based on logical refutations, but its theories are noncausal and, therefore, potentially lacking in scientific value. In contrast, the Lakatosian approach considers causal theories, but it concedes that these theories are not logically refutable. Finally, NMF represents a hybrid approach that subjects Lakatosian causal theories to Popperian logical refutations. However, its tactic of temporarily accepting a ceteris paribus clause during theory testing may be viewed as scientifically inappropriate, epistemically inconsistent, and “completely redundant” (Lakatos, 1978, p. 40). I conclude that the replication “crisis” makes the most sense in the context of the Popperian and NMF approaches because it is only in these two approaches that the failure to replicate a previously corroborated theory represents a logical refutation of that theory. In contrast, such replication failures are less problematic in the Lakatosian approach because they do not logically refute theories. Indeed, in the Lakatosian approach, replication failures can be temporarily ignored or used to motivate theory development. (shrink)

Critics frequently target Ernest Nagel’s model of reduction for its purported inadequacy in addressing the issue of approximation. In response, proponents of Nagel’s model have integrated approximations into the more comprehensive Generalized Nagel-Schaffner model, or the GNS model. However, this article contends that the pertinent criticisms and responses are both misplaced: There are no barriers to Nagel’s model incorporating approximations, and it assimilates them in a manner distinctly dissimilar to the approach of the GNS model. Indeed, Nagel’s model is fundamentally (...) _static_, providing invariant formal and informal conditions for reduction; and it is the _dynamic_ history of science that fulfills relevant conditions for reduction, thereby achieving different _degrees of reductive success_. Consequently, approximations are essentially extraneous to Nagel’s model, since they pertain chiefly to temporally based scientific knowledge and concern merely the _means_ (e.g., approximate or exact deductions) of fulfilling the conditions for reduction within specific problem contexts. This article also develops a Nagelian treatment of approximation, demonstrating how distinctive types of approximations aid in fulfilling various conditions for reduction and contribute to different degrees of reductive success. Two case studies are presented to illustrate the Nagelian treatment: The first examines the specific heat ratio anomaly within the traditional endeavor of reducing thermodynamics to statistical mechanics, and the second addresses the consumption puzzle in the context of reducing macroeconomics to microeconomics. (shrink)

Popper’s (1983, 2002) philosophy of science has enjoyed something of a renaissance in the wake of the replication crisis, offering a philosophical basis for the ensuing science reform movement. However, adherence to Popper’s approach may also be at least partly responsible for the sense of “crisis” that has developed following multiple unexpected replication failures. In this article, I contrast Popper’s approach with that of Lakatos (1978) as well as with a related but problematic approach called naïve methodological falsificationism (NMF; Lakatos, (...) 1978). The Popperian approach is powerful because it is based on logical refutations, but its theories are noncausal and, therefore, potentially lacking in scientific value. In contrast, the Lakatosian approach considers causal theories, but it concedes that these theories are not logically refutable. Finally, NMF represents a hybrid approach that subjects Lakatosian causal theories to Popperian logical refutations. However, its tactic of temporarily accepting a ceteris paribus clause during theory testing may be viewed as scientifically inappropriate, epistemically inconsistent, and “completely redundant” (Lakatos, 1978, p. 40). I conclude that the replication “crisis” makes the most sense in the context of the Popperian and NMF approaches because it is only in these two approaches that the failure to replicate a previously corroborated theory represents a logical refutation of that theory. In contrast, such replication failures are less problematic in the Lakatosian approach because they do not logically refute theories. Indeed, in the Lakatosian approach, replication failures can be temporarily ignored or used to motivate theory development. (shrink)

Discussion of the extraterrestrial hypothesis (ETH), the hypothesis that an extraterrestrial civilization (ETC) is active on Earth today, is taboo in academia, but the assumptions behind this taboo are faulty. Advances in biology have rendered the notion that complex life is rare in our Galaxy improbable. The objection that no ETC would come to Earth to hide from us does not consider all possible alien motives or means. For an advanced ETC, the convergent instrumental goals of all rational agents – (...) self-preservation and the acquisition of resources – would support the objectives of removing existential threats and gathering strategic and non-strategic information. It could advance these objectives by proactively gathering information about and from inhabited planets, concealing itself while doing so, and terminating potential rivals before they become too dangerous. Other hypotheses of ETC behavior, including the zoo/interdict hypothesis and the dark forest hypothesis, also undercut the objection that the ETH is highly improbable. The ETH does not require support from extraordinary evidence because the presence of an ETC on Earth is not highly unlikely and would overturn none of our well-tested scientific knowledge. The fact that most reports of unidentified anomalous phenomena (UAP) have natural or human explanations does not count against it. Inference to the best explanation offers a way to find evidence for this hypothesis, and some evidence for it exists, some of it taking the form of reliable witness reports. The most plausible alternative explanation for some UAP reports declines in probability over time. A hypothesis that is not highly improbable, does not contradict any well-established facts or theories, and explains otherwise unexplained evidence is a rational hypothesis. Since the ETH is a rational hypothesis, investigation of it should not be taboo. (shrink)