Online research in philosophy

Downward causation is commonly held to create problems for ontologically emergent properties. In this paper I describe two novel examples of ontologically emergent properties and show how they avoid two main problems of downward causation, the causal exclusion problem and the causal closure problem. One example involves an object whose colour does not logically supervene on the colours of its atomic parts. The other example is inspired by quantum entanglement cases but avoids controversies regarding quantum mechanics. These examples show that the causal exclusion problem can be avoided, in one case by showing how it is possible to interact with an object without interacting with its atomic parts. I accept that emergence cannot be reconciled with causal closure, but argue that violations of causal closure do not entail violations of the base-level laws. Only the latter would conflict with empirical science.

This paper looks at the main philosophic positions on free will. It suggests that the arguments for causal determinism being compatible with free will can give rise to invalid use of the term "free will". The term "freewillism" is introduced, and the differences between freewillism, determinism and libertarianism are discussed. As is the mechanism whereby freewillism supports free will. A mapping of the philosophic positions on free will to the types of causation is derived, and the evidence supporting the types of causation considered.

The idea of a higher level phenomenon having a downward causal influence on a lower level process or entity has taken a variety of forms. In order to discuss the relation between emergence and downward causation, the specific variety of the thesis of downward causation (DC) must be identified. Based on some ontological theses about inter-level relations, types of causation and the possibility of reduction, three versions of DC are distinguished. Of these, the `Strong' form of DC is held to be in conflict with contemporary science; the `Medium' version of DC may for instance describe thoughts constraining neurophysiological states, while the `Weak' form of DC is physically acceptable but may not in practice be a feasible description of the mind/brain or the cell/molecule relation. All forms have their specific problems, but the Medium and the Weak version seems to be most promising.

With ontology motivated largely by causal considerations, this lucid and provocative work focuses on the idea that physical objects are causally non-redundant. Merricks "eliminates" inanimate composite macrophysical objects on the grounds that they would--if they existed--be at best completely causally redundant. He defends human existence by arguing, from certain facts about mental causation, that we cause things that are not determined by our proper parts. He also provides insight into a variety of philosophical puzzles, while addressing many significant issues like free will, the "reduction" of a composite object to its parts, and the ways in which identity over time can "for practical purposes" be a matter of convention. Anyone working in metaphysics will enjoy this book immensely.

Several theories of emergence will be distinguished. In particular, these are synchronic, diachronic, and weak versions of emergence. While the weaker theories are compatible with property reductionism, synchronic emergentism and strong versions of diachronic emergentism are not. Synchronice mergentism is of particular interest for the discussion of downward causation. For such a theory, a system's property is taken to be emergent if it is irreducible, i.e., if it is not reductively explainable. Furthermore, we have to distinguish two different types of irreducibility with quite different consequences: If, on the one hand, a system's property is irreducible because of the irreducibility of the system's parts' behavior on which the property supervenes, we seem to have a case of "downward causation". This kind of downward causation does not violate the principle of the causal closure of the physical domain. If, on the other hand, a systemic property is irreducible because it is not exhaustively analyzable in terms of its causal role, downward causation is not implied. Rather, it is dubitable how unanalyzable properties might play any causal role at all. Thus, epiphenomenalism seems to be implied. The failure to keep apart the two kinds of irreducibility has muddled recent debate about the emergence of properties considerably.

The importance of downward causation lies in showing that it shows that functional properties such as mental properties are real, although they cannot be reduced to physical properties. Kim rejects nonreductive physicalism, which includes leading functionalism, by eliminating downward causation, and thereby returns to reductionism. In this paper, I make a distinction between two aspects of function—functional meaning and functional structure and argue that functional meaning cannot be reduced to the physical level whereas functional structure can. On this basis, I further distinguish between the integer of the function, which includes the functional meaning and the functional structure, and the whole of the functional realization, and also among the strong, medial, and weak supervenience relations. So-called downward causation is indeed the relationship between the whole of the functional realization and its physical realizer, which is a whole-part relation instead of a relation between levels. As a result of understanding downward causation in this way and abandoning the principle of the causal closure of the physical world, Kim’s argument becomes invalid and nonreductive functionalism, justified.

The dominant position in Philosophy of Science contends that downward causation is an illusion. Instead, we argue that downward causation doesn’t introduce vicious circles either in physics or in biology. We also question the metaphysical claim that “physical facts fix all the facts.” Downward causation does not imply any contradiction if we reject the assumption of the completeness and the causal closure of the physical world that this assertion contains. We provide an argument for rejecting this assumption. Furthermore, this allows us to reconsider the concept of diachronic emergence.

Experimental investigation of mechanisms seems to make use of causal relations that cut across levels of composition. In bottom-up experiments, one intervenes on parts of a mechanism to observe the whole; in top-down experiments, one intervenes on the whole mechanism to observe certain parts of it. It is controversial whether such experiments really make use of interlevel causation, and indeed whether the idea of causation across levels is even conceptually coherent. Craver and Bechtel have suggested that interlevel causal claims can be analysed in a causal and a non-causal component. I accept this idea but argue that their account should be modified so as to account of cases of apparent downward causation. First, constitution must be distinguished from identity; second, the analysis of downward causation requires the concept of a partial constraint. An analysis along these lines shows that the possibility of downward causation is not refuted by Kim's argument according to which it is incompatible with the completeness of physics.

The purpose of this paper is to lay bare the major problems underlying the concept of downward causation as discussed within the perspective of the present interest for phenomena that are characterized by self-organization. In our Discussion of the literature, we have focussed on two questions: (1) What sorts of things are said to be, respectively, causing and caused within the context of downward causation? And (2) What is the meaning of 'causing' in downward causation? We have concluded that the concept of 'downward causation' is muddled with regard to the meaning of causation and fuzzy with regard to the nature of the causes and the effects. Moreover, we have concluded that 'causation' in respect of 'downward causation' is usually understood in terms of explanation and determination rather than in terms of causation in the sense of 'bringing about'. Thus, the term 'downward causation' is badly chosen.