Maarten Van Dyck

Ampliative Adaptive Logics and the Foundation of Logic-Based Approaches to Abduction

In this paper, we propose a reconstruction of logic-based approaches to abductive reasoning in terms of ampliative adaptive logics. A main advantage of this reconstruction is that the resulting logics have a proof theory. As abductive reasoning is non-monotonic, the latter is necessarily dynamic (conclusions derived at some stage may at a later stage be rejected). The proof theory warrants, however, that the conclusions derived at a given stage are justified in view of the insight in the premises at that stage. Thus, it even leads to justified conclusions for undecidable fragments. Another advantage of the proposed logics is that they are much closer to natural reasoning than the existing systems. Usually, abduction is viewed as a form of “backward reasoning”. The search procedure by which this is realized (for instance, some form of linear linear resolution) is very different from the search procedures of human reasoners. The proposed logics treat abduction as a form of “forward reasoning” (Modus Ponens in the “wrong direction”). As a result, abductive steps are very natural, and are moreover nicely integrated with deductive steps. We present two new adaptive logics for abduction, and illustrate both with some examples from the history of the sciences (the discovery of Uranus and of Neptune). We also present some alternative systems that are better suited for non-creative forms of abductive reasoning.

Unification And Explanation

In this article we criticize two recent articles that examinethe relation between explanation and unification. Halonen and Hintikka (1999), on the one hand,claim that no unification is explanation. Schurz (1999), on the other hand, claims that all explanationis unification. We give counterexamples to both claims. We propose a pluralistic approach to the problem:explanation sometimes consists in unification, but in other cases different kinds of explanation(e.g., causal explanation) are required; and none of these kinds is more fundamental.

The paradox of conceptual novelty and Galileo's use of experiments

Starting with a discussion of what I call ‘Koyre’s paradox of conceptual novelty’, I introduce the ideas of Damerow et al. on the establishment of classical mechanics in Galileo’s work. I then argue that although their view on the nature of Galileo’s conceptual innovation is convincing, it misses an essential element: Galileo’s use of the experiments described in the first day of the Two New Sciences. I describe these experiments and analyze their function. Central to my analysis is the idea that Galileo’s pendulum experiments serve to secure the reference of his theoretical models in actually occurring cases of free fall. In this way, Galileo’s experiments constitute an essential part of the meaning of the new concepts of classical mechanics.Starting with a discussion of what I call ‘Koyré’s paradox of conceptual novelty’, I introduce the ideas of Damerow et al. on the establishment of classical mechanics in Galileo’s work. I then argue that although their view on the nature of Galileo’s conceptual innovation is convincing, it misses an essential element: Galileo’s use of the experiments described in the first day of the Two New Sciences. I describe these experiments and analyze their function. Central to my analysis is the idea that Galileo’s pendulum experiments serve to secure the reference of his theoretical models in actually occurring cases of free fall. In this way, Galileo’s experiments constitute an essential part of the meaning of the new concepts of classical mechanics.

Dynamics of Reason and the Kantian Project

I show why Michael Friedman’s idea that we should view new constitutive frameworks introduced in paradigm change as members of a convergent series introduces an uncomfortable tension in his views. It cannot be justified on realist grounds, as this would compromise his Kantian perspective, but his own appeal to a Kantian regulative ideal of reason cannot do the job either. I then explain a way to make better sense of the rationality of paradigm change on what I take to be Friedman’s own terms.I show why Michael Friedman’s idea that we should view new constitutive frameworks introduced in paradigm change as members of a convergent series introduces an uncomfortable tension in his views. It cannot be justified on realist grounds, as this would compromise his Kantian perspective, but his own appeal to a Kantian regulative ideal of reason cannot do the job either. I then explain a way to make better sense of the rationality of paradigm change on what I take to be Friedman’s own terms.

Idealization and Galileo's Proto-Inertial Principle

Galileo proposed what has been called a proto-inertial principle, according to which a body in horizontal motion will conserve its motion. This statement is only true in counterfactual circumstances where no impediments are present. This article analyzes how Galileo could have been justified in ascribing definite properties to this idealized motion. This analysis is then used to better understand the relation of Galileo’s proto-inertial principle to the classical inertial principle.Galileo proposed what has been called a proto-inertial principle, according to which a body in horizontal motion will conserve its motion. This statement is only true in counterfactual circumstances where no impediments are present. This article analyzes how Galileo could have been justified in ascribing definite properties to this idealized motion. This analysis is then used to better understand the relation of Galileo’s proto-inertial principle to the classical inertial principle.

Motion and Proportion in Simon Stevin’s Mechanics

This paper offers a reassesment of Simon Stevin’s mechanics, by focusing on how Stevin tries to anchor his mathematical demonstrations in the behavior of material instruments. It is shown how his views on the relation between spiegheling (speculation) and daet (practice) are crucial to correctly understand his famous proof of the law of the inclined plane and his experimental test of the Aristotelian law of free fall. The distance separating spiegheling and daet is reproduced in that between instruments at rest and instruments in motion, because of Stevin’s claim that impediments to motion are “inseperable accidents” of all moving objects.

Being in or Getting at the Real: Kochan on Rouse, Heidegger and Minimal Realism

We discuss Kochans recent criticism of the work of Joseph Rouse (Kochan 2011). We argue that Kochan fails to show that both Rouses own work and his Heidegger interpretation are plagued by insurmountable problems. We also try to locate the deeper, meta-philosophical reasons that are responsible for what we take to be Kochans misreading of Rouses work. This allows us to throw some light on the standoff that so often seems to characterize debates on scientific realism.