Coalgebraic Components in a Many-Sorted Microcosm ---------------------------------------------------------- Ichiro Hasuo, Chris Heunen, Bart Jacobs, and Ana Sokolova ---------------------------------------------------------- Abstract: --------------------------------------------------------------------------------------------- The microcosm principle, advocated by Baez and Dolan and formalized for Lawvere theories lately by three of the authors, has been applied to coalgebras in order to describe compositional behavior systematically. Here we further illustrate the usefulness of the approach by extending it to a many-sorted setting. Then we can show that the coalgebraic component calculi of Barbosa are examples, with compositionality of behavior following from microcosm structure. The algebraic structure on these coalgebraic components corresponds to variants of Hughes’ notion of arrow, introduced to organize computations in functional programming. ----------------------------------------------------------------------------------------------