42,601 research outputs found
Not without justification
In this paper I take issue with Jonathan Sutton's attempt at defending the thesis that knowledge is justified belief. I argue, first, that the arguments he adduces in support of it fail. Second, I provide independent reason to believe that knowledge and justified belief come apart
Classical invariantism and the puzzle of fallibilism
This paper revisits a puzzle that arises for theories of knowledge according to which one can know on the basis of merely inductive grounds. No matter how strong such theories require inductive grounds to be if a belief based on them is to qualify as knowledge, there are certain beliefs (namely, about the outcome of fair lotteries) that are based on even stronger inductive grounds, while, intuitively, they do not qualify as knowledge. This paper discusses what is often regarded as the most promising classical invariantist solution to the puzzle, namely, that beliefs about the outcomes of fair lotteries do not qualify as knowledge because they are too lucky to do so (or, relatedly, because they do not satisfy a safety condition on knowledge), while other beliefs based on potentially weaker inductive grounds are not too lucky (or, relatedly, because they are safe). A case is presented that shows that this solution to the puzzle is actually not viable. It is argued that there is no obvious alternative solution in sight and that therefore the puzzle still awaits a classical invariantist solution
Understanding phenomena
The literature on the nature of understanding can be divided into two broad camps. Explanationists believe that it is knowledge of explanations that is key to understanding. In contrast, their manipulationist rivals maintain that understanding essentially involves an ability to manipulate certain representations. The aim of this paper is to provide a novel knowledge based account of understanding. More specifically, it proposes an account of maximal understanding of a given phenomenon in terms of fully comprehensive and maximally well-connected knowledge of it and of degrees of understanding in terms of approximations to such knowledge. It is completed by a contextualist semantics for outright attributions of understanding according to which an attribution of understanding is true of one just in case one knows enough about it to perform some contextually determined task. It is argued that this account has an edge over both its explanationist and manipulationist competitors
A problem for contrastivist accounts of knowledge
This paper raises a problem for contrastivist accounts of knowledge. It is argued that contrastivism fails to succeed in providing a modest solution to the sceptical paradox—i.e. one according to which we have knowledge of a wide range of ordinary empirical propositions whilst failing to know the various anti-sceptical hypotheses entailed by them—whilst, at the same time, retaining a contrastivist version of the closure principle for knowledge
Assertion: a function first account
This paper aims to develop a novel account of the normativity of assertion. Its core thesis is that assertion has an etiological epistemic function, viz. to generate knowledge in hearers. In conjunction with a general account of etiological functions and their normative import, it is argued that an assertion is epistemically good if and only if it has the disposition to generate knowledge in hearers. In addition, reason is provided to believe that it makes sense to regulate the practice of assertion by a speaker rule—and, more specifically, by a knowledge rule—as so regulating assertion contributes to ensuring that assertion fulfils its etiological function reliably
Do 'contextualist cases' support contextualism?
This paper addresses the argument from ‘contextualist cases’—such as for instance DeRose’s Bank cases—to attributor contextualism. It is argued that these cases do not make a decisive case against invariantism and that the debate between contextualists and invariantists will have to be settled on broader theoretical grounds
A new pathogen transmission mechanism in the ocean: the case of sea otter exposure to the land-parasite Toxoplasma gondii.
Toxoplasma gondii is a land-derived parasite that infects humans and marine mammals. Infections are a significant cause of mortality for endangered southern sea otters (Enhydra lutris nereis), but the transmission mechanism is poorly understood. Otter exposure to T. gondii has been linked to the consumption of marine turban snails in kelp (Macrocystis pyrifera) forests. It is unknown how turban snails acquire oocysts, as snails scrape food particles attached to surfaces, whereas T. gondii oocysts enter kelp beds as suspended particles via runoff. We hypothesized that waterborne T. gondii oocysts attach to kelp surfaces when encountering exopolymer substances (EPS) forming the sticky matrix of biofilms on kelp, and thus become available to snails. Results of a dietary composition analysis of field-collected snails and of kelp biofilm indicate that snails graze the dense kelp-biofilm assemblage composed of pennate diatoms and bacteria inserted within the EPS gel-like matrix. To test whether oocysts attach to kelp blades via EPS, we designed a laboratory experiment simulating the kelp forest canopy in tanks spiked with T. gondii surrogate microspheres and controlled for EPS and transparent exopolymer particles (TEP - the particulate form of EPS). On average, 19% and 31% of surrogates were detected attached to kelp surfaces covered with EPS in unfiltered and filtered seawater treatments, respectively. The presence of TEP in the seawater did not increase surrogate attachment. These findings support a novel transport mechanism of T. gondii oocysts: as oocysts enter the kelp forest canopy, a portion adheres to the sticky kelp biofilms. Snails grazing this biofilm encounter oocysts as 'bycatch' and thereby deliver the parasite to sea otters that prey upon snails. This novel mechanism can have health implications beyond T. gondii and otters, as a similar route of pathogen transmission may be implicated with other waterborne pathogens to marine wildlife and humans consuming biofilm-feeding invertebrates
- …
