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Philippe Balbiani and Luis Fariñas del Cerro

A relational model of movement.

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Overview of interactions

N:o Question Answer(s) Continued discussion
2 9.1  Erik Sandewall
9.1  Luis Fariñas del Cerro
9.1  Erik Sandewall
9.1  Luis Fariñas del Cerro

Q2. Erik Sandewall:

You are using a geometrically oriented approach. Another approach which has been used by a number of authors, including Shanahan and myself, is to embed differential equations within a first-order logic. This requires a multi-sorted logic with continuous time as one of the sorts; from there on it is a fairly straightforward extension of narrative time-line approaches that use discrete time, which means that it has the advantage or at least the potential of integrating well with solutions to other issues, such as inertia (generalizes to minimization of discontinuities), causality, and concurrency.

Question, therefore: What advantage do you see in the geometrical approach?

A2. Luis Fariñas del Cerro:

I don't think logic has anything to do with continous change.

C2-1. Erik Sandewall:

Certainly it is technically possible to have a logic where the real numbers is one of the sorts, and that's also what we have done. Given that both approaches exist, we ought to be able to compare them.

C2-2. Luis Fariñas del Cerro:

(Additional discussion followed)

This on-line debate page is part of a discussion at recent workshop; similar pages are set up for each of the workshop articles. The discussion is organized by the area Reasoning about Actions and Change within the Electronic Transactions on Artificial Intelligence (ETAI).

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