Epistemic logics typically talk about knowledge of individual agents or groups explicitly listed agents. Often, however, one wishes to express specified by a given property, as in ‘it is common among economists’. We introduce such logic knowledge, which we term abstract-group epistemic (AGEL). That is, AGEL features operator for concepts separate agent that keep generic, with possible being ALC...

This note will present certain algebraic results obtained by Samuel Eilenberg and the author in a study of the relations between homotopy and homology groups of a topological space. These results yield a homology theory for any abelian group II, in which the low dimensional homology and cohomology groups of n correspond to familiar constructions on II. They depend upon the application of the me...