James W. Cornman

Craig's theorem, Ramsey-sentences, and scientific instrumentalism

Des travaux, en serre semi- controlee, ont ete realises dans le but de presenter un etat des differents mecanismes lies a la resistance de deux genotypes de ble dur ( Triticum durum Desf.) a l’oidium ( Blumeria graminis f.sp. tritici). Des plants de ble ont ete inocules au stade six feuilles avec un inoculum provenant d’un champ de ble dur. L’interaction ble / Blumeria graminis a ete abordee sous une approche biochimique par le biais du dosage des sucres solubles et physiologique en etudiant le statut hydrique de la feuille (turgescence cellulaire et transpiration cuticulaire). Les resultats obtenus montrent que l’infection par Blumeria graminis entraine une accumulation significative des sucres solubles chez les feuilles infectees de la variete Waha comparativement aux temoins non inocules. Pour la variete Vitron, une baisse non significative des sucres solubles est enregistree chez les feuilles infectees par rapport aux temoins. En ce qui concerne le statut hydrique, les deux genotypes semblent reagir a l’infection d’une facon similaire par le maintien d’une turgescence cellulaire (R.W.C) elevee des feuilles infectees surtout pour la variete Vitron ou la difference est significative. Pour la perte graduelle en eau ou transpiration cuticulaire (R.W.L), une chute tres hautement significative est notee chez les feuilles infectees de Waha par rapport aux temoins. Ces resultats nous laissent penser que la teneur relative en eau et l’accumulation des sucres solubles peuvent etre pris en consideration comme criteres de selection de genotypes resistants a la maladie. Mots-cles : Blumeria graminis -Ble dur- Sucres solubles - Statut hydrique . An experiment was run in green house under semi controlled conditions, to present an overview of the different mechanisms involved in resistance of two durum wheat genotypes ( Triticum durum Desf.) to powdery mildew ( Blumeria graminis f.sp. tritici). Wheat plants were inoculated at six leaves stage. The wheat/ Blumeria graminis interaction has been approached by biochemical analysis through the determination of soluble sugars and studying physiological water status of the leaf (RWC and RWL). The results show that infection by Blumeria graminis f.sp. tritici causes a significant accumulation of soluble sugars in leaves of the cultivar Waha compared to non inoculated controls. Cultivar Vitron showed a non-significant decrease of soluble sugars in infected leaves compared to controls. As to water status, the two genotypes seem to react to infection in a similar way in maintaining cell turgor (RWC) of leaves infected for Vitron especially where the difference is significant. For the gradual loss of water (RWL), a very high significant decrease was noted in infected leaves for Waha compared to controls. These results suggest that the relative water content and accumulation of soluble sugars may be considered as criteria for selection of genotypes resistant to diseases. Key words : Blumeria graminis- Durum wheat- Soluble sugars- Water status.

Skepticism, Justification, and Explanation.

1 An Argument for the Explanatory Foundational Theory and Against Skepticism.- I: Skepticism and the Foundations of Justification.- 2 Skepticism and a Foundation of Certainty.- 3 Skepticism and Acceptability without Certainty.- 4 Skepticism and the Probability of Nonbasic Statements (I): On Sufficient Conditions for Absolute Probabilities.- 5 Skepticism and the Probability of Nonbasic Statements (II): On Sufficient Conditions for Conditional Probabilities.- II: An Examination of Nonfoundational Theories.- 6 Foundational Versus Nonfoundational Theories of Justification.- 7 A Foundational Theory with Explanatory Coherence.- 8 Explanatory Systems: Conditions of Adequacy and Systemic Tests.- 9 The Systemic Tests of Economy and Simplicity.- 10 The Explanatory Foundational Theory and Skepticism.- 11 Summary and Concluding Remarks.- A Bibliographic Essay (Walter N. Gregory).- Index of Names.- Index of Subjects.

On Justifying Nonbasic Statements by Basic-Reports

One of the crucial problems that faces a foundational theory of justification has been the difficulty of finding some plausible way to warrant inferences from what is foundational to other, nonfoundational statements. Without some such warrant only the very limited foundational statements are justified, and some form of epistemological skepticism seems reasonable. This latter is surely true if the foundation for each person is ‘Cartesian’, that is, consists only of what I call ‘basic-reports’ or first-person reports that concern only present psychological states of that person. This, of course, has traditionally been the foundation, whether for Descartes with a base of what is initially or noninferentially certain, or for C. I. Lewis who also seems to allow some statements that are merely initially acceptable, or for R. M. Chisholm who permits only the ‘directly evident’ at the foundation. It has, unfortunately, been the despair of ever finding a way to extend justification from such a narrow base that has caused many philosophers to flee to some non-foundational theory. But, if what I have argued elsewhere is correct, there is no haven from skepticism there.1 Our only hope — slim as it may seem — lies with some form of foundationalism.

Mind-body identity: Cross-categorial or not?

ConclusionI have tried to accomplish two tasks in this paper. The first, and more important, is to free my defense of the mind-body identity theory against the property objection from reliance on there being categories. The second is to argue that if there are categories, Rosenbaums objections pose no threat to principle (II), or its more plausible relative, (IV). I believe I have finished both tasks. This significantly strengthens my reasons for accepting some form of the identity theory. Of course, deciding whether it is reasonable enough to accept is a much more difficult task. But if what I have argued elsewhere is correct, that task is also completed. We should, at least at present, accept what I call the ‘neutral’ or nonreductive identity theory.

Chisholm on Sensing and Perceiving

Much of Chisholm’s well deserved reputation results from his work in epistemology concerning the definition of ‘S knows that P’, his formulations of epistemic rules, and his defense of a foundational theory of empirical knowledge. Yet I believe that a less noticed area of his work may well have more important consequences for future developments in philosophy. I am referring to his nonepistemic theses about perception, especially his development and defense of the sensing terminology as preferable to the sense-datum terminology, and his analysis of ‘S perceives x’ in terms of sensing. And although these views concern terminology and analysis of certain linguistic phrases, I believe we can see both of them as contributions to what might be called the metaphysics of perception rather than to a theory of perceptual knowledge. My main aim in this paper is to transform his linguistic claims into ‘factual’ or metaphysical claims about perception and to evaluate some of his reasons for his theses. I shall also, however, consider briefly his view of secondary qualities to bring out what seems to be a theory of the nature of the external world as well as our perception of it.