Online research in philosophy

In the literature on scientific explanation, there is a classical distinction between explanations of facts and explanations of laws. This paper is about explanations of facts. Our aim is to analyse the role of unification in explanations of this kind. We discuss five positions with respect to this role, argue for two of them and refute the three others.

This paper pursues two aims. First, to show that the block universe view, regarding the universe as a timelessly existing four-dimensional world, is the only one that is consistent with special relativity. Second, to argue that special relativity alone can resolve the debate on whether the world is three-dimensional or four-dimensional. The argument advanced in the paper is that if the world were three-dimensional the kinematic consequences of special relativity and more importantly the experiments confirming them would be impossible.

Some causal explanations are non-committal in that mention of a property in the explanans conveys information about the causal origin of the explanandum even if the property in question plays no causal role for the explanandum . Programme explanations are a variety of non-committal causal (NCC) explanations. Yet their interest is very limited since, as I will argue in this paper, their range of applicability is in fact quite narrow. However there is at least another variety of NCC explanations, causal orientation explanations, which offer a plausible model for many explanations in the special sciences.

I argue that the wave function ontology for quantum mechanics is an undesirable ontology. This ontology holds that the fundamental space in which entities evolve is not three-dimensional, but instead 3N-dimensional, where N is the number of particles standardly thought to exist in three-dimensional space. I show that the state of three-dimensional objects does not supervene on the state of objects in 3N-dimensional space. I also show that the only way to guarantee the existence of the appropriate mental states in the wave function ontology has undesirable metaphysical baggage: either mind/body dualism is true, or circumstances which we take to be logically possible turn out to be logically impossible.While our theory can be extended formally in a logically consistent way by introducing the concept of a wave in a 3N-dimensional space, it is evident that this procedure is not really acceptable in a physical theory... (Bohm 1957, 117).

We discuss whether low-dimensional chaos and even nonlinear processes can be traced in the electrical activity of the brain. Experimental data show that the dimensional complexity of the EEG decreases during event-related potentials associated with cognitive effort. This probably represents increased nonlinear cooperation between different neural systems during sensory information processing.

It is perfectly possible to think of things and processes as four-dimensional space-time entities. The instantaneous state of such a four-dimensional spacetime solid will be a three-dimensional “time slice” of the four-dimensional solid. Then instead of talking of things or processes changing or not changing we can now talk of one time slice of a four-dimensional entity being different or not different from some other time slice. (Note the tenseless participle of the verb ‘to be’ in the last sentence.) (Smart, p. 95).

Two-dimensional semantics is a theory in the philosophy of language that provides an account of meaning which is sensitive to the distinction between necessity and apriority. Usually, this theory is presented in an informal manner. In this thesis, I take first steps in formalizing it, and use the formalization to present some considerations in favor of two-dimensional semantics. To do so, I define a semantics for a propositional modal logic with operators for the modalities of necessity, actuality, and apriority that captures the relevant ideas of two-dimensional semantics. I use this to show that some criticisms of two-dimensional semantics that claim that the theory is incoherent are not justified. I also axiomatize the logic, and compare it to the most important proposals in the literature that define similar logics. To indicate that two-dimensional semantics is a plausible semantic theory, I give an argument that shows that all theorems of the logic can be philosophically justified independently of two-dimensional semantics.

Multicellular organisms are ensembles of quasi-two-dimensional structures (sheets) of various kinds. Why should the development of all organisms be mediated by a quasi-two-dimensional structure? Why does such development avoid a direct confrontation with the third dimension? In this paper, we accept the challenge of addressing this question from the perspective of computational geometry and suggest that the construction of three-dimensional organisms may be explained by the constraints imposed on a bottom-up construction process.

This paper investigates the tenability of wavefunction realism, according to which the quantum mechanical wavefunction is not just a convenient predictive tool, but is a real entity figuring in physical explanations of our measurement results. An apparent difficulty with this position is that the wavefunction exists in a many-dimensional configuration space, whereas the world appears to us to be three-dimensional. I consider the arguments that have been given for and against the tenability of wavefunction realism, and note that both the proponents and the opponents assume that quantum mechanical configuration space is many-dimensional in exactly the same sense in which classical space is three-dimensional. I argue that this assumption is mistaken, and that configuration space can be taken as three-dimensional in a relevant sense. I conclude that wavefunction realism is far less problematic than it has been taken to be. Introduction Non-separability The instantaneous solution The dynamical solution Invariance What is configuration space, anyway? Conclusion.

This paper investigates the tenability of wavefunction realism, according to which the quantum mechanical wavefunction is not just a convenient predictive tool, but is a real entity figuring in physical explanations of our measurement results. An apparent difficulty with this position is that the wavefunction exists in a many-dimensional configuration space, whereas the world appears to us to be three-dimensional. I consider the arguments that have been given for and against the tenability of wavefunction realism, and note that both the proponents and opponents assume that quantum mechanical configuration space is many-dimensional in exactly the same sense in which classical space is three-dimensional. I argue that this assumption is mistaken, and that configuration space can be taken as three-dimensional in a relevant sense. I conclude that wavefunction realism is far less problematic than it has been taken to be.