Andreas Hüttemann

It is my aim in this paper to look at some of the arguments that are brought forward for or against certain claims to unity/disunity (in particular to examine those arguments from science and from scientific practice) in order to evaluate whether they really show what they claim to. This presupposes that the concept or rather the concepts of the unity of physics are reasonably clear. Three concepts of unity can be identified: (1) ontological unity, which refers to the objects physics is about; (2) descriptive unity, which addresses the descriptive devices physics employs in dealing with physical systems (3) unity of practice, which deals with what physicists actually do.

We address the question whether there is an explanation for the fact that as Fodor put it the micro-level “converges on stable macro-level properties”, and whether there are lessons from this explanation for other issues in the vicinity. We argue that stability in large systems can be understood in terms of statistical limit theorems. In the thermodynamic limit of infinite system size N → ∞ systems will have strictly stable macroscopic properties in the sense that transitions between different macroscopic phases of matter (if there are any) will not occur in finite time. Indeed stability in this sense is a consequence of the absence of fluctuations, as (large) fluctuations would be required to induce such macroscopic transformations. These properties can be understood in terms of coarse-grained descriptions, and the statistical limit theorems for independent or weakly dependent random variable describing the behaviour averages and the statistics of fluctuations in the large system limit. We argue that RNG analyses applied to off-critical systems can provide a rationalization for the applicability of these limit theorems. Furthermore we discuss some related issues as, for example, the role of the infinite-system idealization.

This paper tries to get a grip on two seemingly conflicting intuitions about reductionism in quantum mechanics. On the one hand it is received wisdom that quantum mechanics puts an end to ‘reductionism’. Quantum-entanglement is responsible for such features of quantum mechanics as holism, the failure of supervenience and emergence. While I agree with these claims I will argue that it is only part of the story. Quantum mechanics provides us with thorough-going reductionist explanations. I will distinguish two kinds of micro-explanation (or micro-‘reduction’). I will argue that even though quantum-entanglement provides an example for the failure of one kind of micro-explanation it does not affect the other. Contrary to a recent paper by Kronz and Tiehen I claim that the explanation of the dynamics of quantum mechanical systems is just as reductionist as it used to be in classical mechanics.

In diesem Aufsatz untersuche sich, ob sich der Hobbes’sche Naturzustand als Gefangenendilemma beschreiben lässt und welche Konsequenzen dies gegebenenfalls hat. Ich argumentiere für die Thesen, dass erstens eine solche Beschreibung eine angemessene Charakterisierung des Hobbes’schen Naturzustandes ist , dass das Gefangenendilemma zweitens kein Problem für die Hobbes’sche Argumentation aufwirft und dass drittens Hobbes sein Argumentationsziel verfehlte, wenn er den Naturzustand anders beschriebe, d.h. so, als seien die Applikationsbedingungen des Gefangenendilemmas nicht erfüllt. Das Gefangenendilemma, in dem sich die Naturzustandsbewohner befinden, ist daher notwendige Voraussetzung für die Vernünftigkeit eines Staates, in dem der Souverän mit einer Hobbes’schen Machtfülle ausgestattet ist

Earman and Roberts claim that there is neither a persuasive account of the truth-conditions of ceteris paribus laws, nor of how such laws can be confirmed or disconfirmed. I will give an account of the truth conditions of ceteris paribus laws in physics in terms of dispositions. It will meet the objections standardly raised against such an account. Furthermore I will elucidate how ceteris paribus laws can be tested in physics. The essential point is that physics provides methodologies for dealing with disturbing factors. For this reason disturbing factors need not be listed explicitly in law-statements. In virtue of the methodologies it is possible to test how systems would behave if the disturbing factors were absent. I will argue that this suffices to establish the tenability of the dispositional account of ceteris paribus laws

In this paper I will introduce a problem for at least those Humeans who believe that the future is open. More particularly, I will argue that the following aspect of scientific practice cannot be explained by openfuture- Humeanism: There is a distinction between states that we cannot bring about (which are represented in scientific models as nomologically impossible) and states that we merely happen not to bring about. Open-future-Humeanism has no convincing account of this distinction. Therefore it fails to explain why we cannot bring about certain states of affairs, it cannot explain what I call the “recalcitrance of nature”.

In this paper I take a look at what I take to be the best argument for dispositions. According to this argument we need dispositions in order to understand certain features of scientific practice. I point out that these dispositions have to be continuously manifestable. Furthermore I will argue that dispositions are not the causes of their manifestations. However, dispositions and causation are closely connected. What it is to be a cause can best be understood in terms of counterfactuals that are based on dispositions.

Laws are supposed to tell us how physical systems actually behave. The analysis of an important part of physical practice--abstraction--shows, however, that laws describe the behavior of physical systems under very special circumstances, namely when they are isolated. Nevertheless, laws are applied in cases of non-isolation as well. This practice requires an explanation. It is argued that one has to assume that physical systems have dispositions. I take these to be innocuous from an empiricist's standpoint because they can--at least in principle--be measured. Laws can be applied whenever such a disposition is present, they describe how the physical system would behave if the disposition were manifest.

Given certain well-known observations by Mach and Russell, the question arises what place there is for causation in the physical world. My aim in this chapter is to understand under what conditions we can use causal terminology and how it fi ts in with what physics has to say. I will argue for a disposition-based process-theory of causation. After addressing Mach’s and Russell’s concerns I will start by outlining the kind of problem the disposition based process-theory of causation is meant to solve. In a second step I will discuss the nature of those dispositions that will be relevant for our question. In section 3 I will discuss existing dispositional accounts of causation before I proceed to present my own account (sections 4 to 6) and contrast it with traditional process-theories (section 7).

Moritz Schlick dealt with the question of causality in various places, including in his Allgemeine Erkenntnislehre - but especially in two essays that appeared in the journal Die Naturwissenschaften in 1920 and 1931. I will deal here with the essay "Naturphilosophische Betrachtungen über das Kausalprinzip" from 1920. First, in the first section, I will present the historical context and thus the problems to which Schlick was responding. In the second and third sections, I will reconstruct and discuss Schlick's proposed solutions to these problems.