Solution Generating Technique for Noncommutative Orbifolds

We propose the relationships between the noncommutative solitons and the (fractional) D-branes on the C^2/Z_n orbifold and extend the solution generating technique for the orbifold. As applications, we determine how tachyon condensations occur in various D-Dbar systems on the orbifolds. The calculations give results consistent with BSFT. The extended solution generating technique enables us to calculate more general decay modes of D-Dbar systems.Comment: 13 pages, 1 figur

Modals and Modal Epistemology

I distinguish (§1) two projects in modal epistemology—one about how we come to know modal truths, and one about why we have the ability so to come to know. The latter, I suggest, (§§2–3) is amenable to an evolutionary treatment in terms of general capacities developed to evaluate quotidian modal claims. I compare (§4) this approach to a recent suggestion in a similar spirit by Christopher Hill and Timothy Williamson, emphasizing counterfactual conditionals instead of quotidian modals; I argue that while there are some reasons to prefer the quotidian modals approach, there are none favoring the Hill/Williamson counterfactual approach. I conclude (§5) with a suggestion that the remaining questions both approaches leave unanswered ought not to be too troubling

Contextual Injustice

Contextualist treatments of clashes of intuitions can allow that two claims, apparently in conflict, can both be true. But making true utterances is far from the only thing that matters — there are often substantive normative questions about what contextual parameters are appropriate to a given conversational situation. This paper foregrounds the importance of the social power to set contextual standards, and how it relates to injustice and oppression, introducing a phenomenon I call "contextual injustice," which has to do with the unjust manipulation of conversational parameters in context-sensitive discourse. My central example applies contextualism about knowledge ascriptions to questions about knowledge regarding sexual assault allegations, but I will also discuss parallel dynamics in other examples of context-sensitive language involving politically significant terms, including gender terms. The central upshot is that the connections between language, epistemology, and social justice are very deeply interlinked

Internalism, Factivity, and Sufficient Reason

How radical is the idea that reasons are factive? Some philosophers consider it a dramatic departure from orthodoxy, with surprising implications about the bearing of the external world on what credences it’s reasonable to have, what beliefs are epistemically appropriate, and what actions are rational. I deny these implications. In the cases where external matters imply differences in factive states, there will inevitably be important weaker factive states in common. For example, someone who knows it is raining has many factive states in common with someone who has a Gettiered belief that it is raining, or one who falsely but justifiably believes that it is raining. The factive reasons denied to subjects in Gettier cases or skeptical scenarios are in an important sense redundant; appropriate belief or action supervenes on internal states, even if reasons must be factive (and even if appropriate belief and action supervenes on reasons). The degree to which the strategy is applicable depends substantively on epistemic assumptions about basic or foundational knowledge. I argue that even given a significantly externalist approach to the latter internalist intuitions about rational credence, belief, and action can be vindicated