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Showing posts from September, 2015

Are some logics universally impossible?

Leibniz and Whitehead as ontologists of agents and on metaphysicians of perspective agree that when we consider the whole process (or the whole class of monads) there are no contradictions. Yet, finite beings can only coordinate what they perceive within perspectives and are guided by finite lab-like simplifications of the whole. These simplifications cannot be taken apart from the whole, and yet they provide some sort of mathesis localis . Maybe we can think of different logical systems in this way: they capture something but only by failing to be fully coordinated with all the rest. In our investigation of galaxies (classes of possible worlds associated to each logic), we are now wondering whether there are classes of possible world (that we call constellations) that cannot be galaxies. That is, there is no signature F of formulae that could formulate a logic that would make possible exactly the worlds in these constellation. Take a constellations formed by two or more worlds with

Conversation and animation

I've been thinking about what is at stake in conversations. Conversations are frictions of perspectives - they could involve many or just two parts, but not one. They are very different from simple apprehensions of information - something like a mirror image of what is being conveyed. In fact, conversations are not really about conveying anything, monologues get a message through, conversations have a different geometry. Grice's implicatures show that in a conversation interaction there are expectations built both from the conversation history and from the very structure of what a relevant, cooperative, well-mannered, qualitative and quantitative contributive dialogue is supposed to be. What is said in a conversation wouldn't mean the same or even make sense outside the frame of that conversation - contexts are part of the message. It seems further that there is no message without context (and no capture without coordination) for often the only way to find out is to go and

Slow activism

Last week I went to "Desfazendo GĂȘnero", a queer event in Bahia bringing together activists and people reflecting on undoing gender. It was a tense event. Internal disputes framed by a hostile external environment in a reactionary country made it explosive. Keynote was given by Judith Butler who wise enough to sense the atmosphere and defend the rhythm of theory in a very elegant way. Theory building is slow and piecemeal thinking of alternatives and production of different tonalities. Theory construction is slower than usual activism because it can be read as slowed down territory where we can afford some attitudes otherwise difficult and rare. It can afford, above all, gestures of hospitality.

The plurality of formalities

In my work on logical compatibilities and classes of possible worlds (together with Alexandre, Rodrigo and Edelcio) we were led to tackle with the ambiguities in the current use of the notion of a possible world. Sometimes the expression is used to mean whatever is compatible with a given logic - and therefore given, say, classical propositional logic, a single possible world would be so that the snow is white or not. I'm inclined to refer to these uses of "possible world" with the alternative name of "world scheme". A world scheme reveals what is compatible with a given logic but a class of possible world in the sense that different world are compatible with the same logic is what we call a galaxy of a logic and it is can be seen as its ontological counterpart in the space of world. The study of galaxies opens some interesting horizons, one of them - which we haven't explored thoroughly yet - is the very issue of real contradictions, that is of the ontolo