We are happy to invite you to the symposium Logic and Culture organized by the VVL (Nederlandse Vereniging voor Logica en Wijsbegeerte der Exacte Wetenschappen) which will take place
Friday April 8, 2011
Hoog Brabant (how-to-get-there), Utrecht
|11.00||Dov Gabbay||Future Oriented Determination of Entities in Talmudic Logic|
|12.00||lunch and general meeting|
|13.00||Sara Uckelman||Logic and Interaction in the Middle Ages|
|14.00||tea and coffee|
|14.30||Michiel Leezenberg||Logic in Islamitic Thought|
|15.30||tea and coffee|
|16.00||Henk Barendregt||Attention to consciousness and corollaries|
Dov Gabbay (King's College London, UK)
Title: Future Oriented Determination of Entities in Talmudic Logic
Abstract: Ordinary dynamic action logics deal with states and actions upon states. The actions can be deterministic or non-deterministic, but it is always assumed that thepossible results of the actions are clear cut. Talmudic logic deals with actions (usually legally meaningful actions which can change the legal status of an entity) which may be not clear cut and need clarifications. The clarification is modelled by public announcement which comes at a later time after the action has taken place. The model is further complicated by the need to know what is the status of formulas at a time before the results of the action is clarified, as we do not know at which state we are in. Talmudic logic treats such states much like the quantum superposition of states and when clarification is available we get a projection onto a pure state. The Talmudic lack of clarity of actions arises from applying an action to entities defined using the future, like `Let the man who will win the jackpot in lottery next week be the sole heir in my will now'. We need to wait a week for the situation to clarify. There is also the problem of legal backwards causality, as this man, if indeed he exists, unaware of his possible good fortune, may have himself meanwhile donated all his property to a charity. This paper will offer a model and a logic which can represent faithully the Talmudic reasoning in these matters. We shall also see that we get new types of public announcement and quantum action logics.
Sara Uckelman (UvA)
Title: Logic and Interaction in the Middle Ages
Abstract: Logic is traditionally viewed as a single-person enterprise, with "logician" conjuring up images of an academic sitting alone at his desk, scribbling proofs and theorems on a piece of paper. But recently, there has been a shift in emphasis in logic research from static, monological systems to dynamic, dialogical systems, where logical reasoning is a type of interaction between two or more players in a game. This idea is, however, not new: This interactive approach to logic and inference was the focus of one of the primary innovations of logicians in the High Middle Ages (13th-15th C) in Western Europe. We discuss the role of logic in medieval society, both academic and ecclesiastic, and introduce medieval theories of obligationes, a type of logical disputation game, to illustrate the dialogical and multi-player character of logic in the Middle Ages.
Michiel Leezenberg (UvA)
Title: Logic in Islamitic Thought
Abstract: In classical Islamic civilization, logic knew some gifted students, and had ardent supporters as well as fierce opponents. In this contribution, I will briefly discuss the changing character and status of logic in the premodern Muslim world. Peripatetic philosophers made great efforts towards further refining Aristotelian syllogistic; but there was also an anti-Aristotelian undercurrent basing itself on the Stoic-inspired logic that could be found in speculative theology (kalâm) and jurisprudence (fiqh). Inspired by this undercurrent, the twelfth-century thinker Shihâb al-Dîn al- Suhrawardî developed a notion of `knowledge by presence'(`ilm al-hudûrî'), which displays some intriguing similarities with David Kaplan's notion of direct reference. I will conclude with some observations of logic's Werdegang in the Muslim world. Conventional wisdom has it that logic, along with philosophy and the natural sciences, disappeared from the Islamic in the thirteenth century at the latest; but in fact, Aristotelian syllogistic continued to be studied by religious scholars for many centuries; and in the Shi’ite world, it never disappeared at all. Recent research suggests that the demise of interest in logic in the Sunni world is, in fact, of a very recent date.
Henk Barendregt (RU)
Title: Attention to consciousness and corollaries
Abstract: This talk is about what is arguably the essence of Buddhism. Consciousness always has an object and a state. Like for Turing Machines, the state is of essential importance: it determines what is our behaviour, the next object, and next state. There are positive and negative states, depending whether suffering decreases or increases. Meditation has as goal to improve states, either by increasing positive states (concentration meditation) or by decreasing negative states (insight meditation). The way to reach this is by increasing attention in the form of concentration, the ability keep focussed on an object, and mindfulness, the ability to know where our attention is. One milestone of insight meditation consists of being able to see that consciousness is a discrete (pulsating) deterministic process. This goes against our belief in agency, the illusion that we are in control of things. As a result the practitioner precieves fear, danger, and disenchantment. The next milestone, requiring work, is to obtain temporary equanimity about the mentioned phenomena. After that the next milestone, obtained though 'surrendering', is to see that our clinging to agency is unnecessary. There is nothing to defend, as agency is an illusion.
This has far reaching consequences for our being in the world. It increases peace, with oneself, others and the universe. The reason for this is that without the need to defend the non-existing agency, provides a considerably increased degree of freedom. As further corollaries there are insights in the scientific view on consciousness. It unifies the Simon-Newell and connectionist views on intelligence. Moreover, it has led to a better understanding of the role of the cerebrospinal fluid for mind states.