Markus Schrenk

This essay attempts to demonstrate that it is doubtful if Galileo's famous thought experiment concerning falling bodies in his 'Dialogues Concerning Two New Sciences' (Galileo 1954: 61-64) actually does succeed in proving that Aristotle was wrong in claiming that "bodies of different weight […] move […] with different speeds which stand to one another in the same ratio as their weights," (Galileo 1954: 61). (Part I); and further that it is likewise doubtful that that argument does or even can establish Galileo's own famous 'Law of Falling Bodies,' viz., that regardless of their weight all bodies fall with the same speed. (Part II).

Since the mid-90s dispositionalism, the view that dispositions are irreducible, real properties, gained strength due to forceful counterexamples (finks and antidotes) that could be launched against Humean anti-dispositionalist attempts to reductively analyse dispositional predicates. In the light of these anti-Humean successes, and in combination with ideas surrounding metaphysical necessity put forward by Kripke and Putnam, some dispositionalists felt encouraged to propose a strong anti-Humean view under the name of “Dispositional Essentialism”. In this paper, I show that, ironically, the counterexamples dispositionalists have used against the Humean reductive analysis of dispositional predicates also prove to be problems for a strong form of dispositional essentialism that assimilates dispositionality and metaphysical necessity. Help comes from an unlike ally—Carnapian reductions sentences—but the alliance is not unproblematic.

Many philosophers of science think that most laws of nature (even those of fundamental physics) are so called ceteris paribus laws, i.e., roughly speaking, laws with exceptions. Yet, the ceteris paribus clause of these laws is problematic. Amongst the more infamous difficulties is the danger that 'For all x: Fx ⊃ Gx, ceteris paribus' may state no more than a tautology: 'For all x: Fx ⊃ Gx, unless not'. One of the major attempts to avoid this problem (and others concerning ceteris paribus laws) is to claim that the subject matter of laws are ascriptions of dispositions, powers, capacities etc., and not the regular behaviour we find in nature. That we do not know whether the cetera are paria in a specific situation does not matter to the dispositionalist because the objects have the disposition regardless of the circumstances. The defence of the latter claim is that dispositions can be instantiated without being manifested. Hence, the laws that ascribe dispositions are strict and it looks as if they do not face the above mentioned problems of ceteris paribus laws. In this essay I attempt to show that these assumptions are wrong. I hope to illustrate that not only does the ceteris paribus clause reoccur inside the dispositions, moreover, there are laws—laws about non-fundamental entities with instable dispositions—which bear a ceteris paribus clause that cannot be hidden in a disposition.