The last talk for the year within the cycle of online seminars organized by the Milan Logic Group will be given by Vito Michele Abrusci on December 3rd, 2020, at 10:30 via Zoom. Please contact us for details for joining and stay tuned to this website for upcoming news on events for 2021.
Discoveries on syllogisms, induced by linear logic, will be presented:
a) Categorical Propositions and Syllogisms are closed under duality. The system of Aristotelian syllogisms (1st, 2nd and 3rdfigures) is complete under duality.
b) Categorical Propositions and Syllogisms may be represented inside multiplicative fragment of Linear Logic (no need of contraction and weakening rules, no need of first order quantifiers). Better understanding of the Aristotelian notion of “contradictory propositions”.
c) Syllogisms as proof-nets, and thus as geometrical objects and as programs.
d) Why 1st figure syllogisms are simple syllogisms, and the other syllogisms are not simple? A geometrical answer: 1st figure syllogisms are planar proof-nets, whereas other syllogisms are not planar proof-nets.
e) Reductions of syllogisms to 1st figure syllogisms are geometrical ways to transform non-planar graphs into planar graphs.
In this talk, I will discuss logics for social networks, their epistemic extensions, and dynamics in such structure, including diffusion as modeled by threshold models. I will present a selection of recent models for social networks and their epistemics, with a focus on how these may be represented using dynamic term-modal logic (DTML)—a dynamic, quantified modal/epistemic logic, where the subscripts of operators are first-order terms, allowing formulas such as $\exist x K_x N(x,b)$: there exists and agent that knows that it is networked with agent b. DTML is based on an enriched version of action models of dynamic epistemic logic fame, and comes with a complete set of reduction axioms. Modelling social network dynamics in DTML thus directly provide sound and complete logics. Additionally, such logics are decidable when only a finite set of agents is considered.
The Logic Group successfully started its Seminar Series online on Teams last week. On 19/03 Pere Pardo gave a talk on “Towards a Tractable Epistemic Logic”. We will reschedule guest lectures and add group’s members lectures. The talks will be open to attend with a shared link. Monitor this website or contact us for updates.