Externalism is the thesis that the mind does not supervene exclusively on the intrinsic state of the subject. I shall consider three types of externalism and examine how they are related to each other: (i) content externalism, (ii) vehicle externalism, and (iii) direct realism. Content externalism derives from Putnam's Twin-Earth intuitions that purported to show that the reference and truth conditions of mental-state ascriptions are externally determined. This type of externalism is widely taken to apply to the contents of mental representations generally. The second type of externalism has been argued for in Clark & Chalmers' paper 'The Extended Mind' and derives from the dynamics of cognition. The basic idea is that some of the external representations we employ to solve our cognitive tasks deserve to be characterized as mental representations, despite their external location. I shall argue that both types of externalism are unsupported, due to a characterization of the mental according to which consciousness is inessential. Content externalism draws upon a consciousness-independent, causal-historical theory of intentionality. Vehicle externalism illegitimately treats external representations of which the subject is not conscious as parts of mental processes. This brings us to the third type of externalism, direct realism, most closely related to John Campbell's relational view on consciousness. Direct realism draws upon the common-sense idea that perceptual experience relates us in an immediate way to the external objects we perceive and proposes that these external objects are literally constituents of the contents of experience. I shall argue that direct realism suggests a radically different conception of consciousness, as a property of subjects rather than a property ascribed to a particular class of mental representations. Furthermore, I shall argue that both content externalism and vehicle externalism in fact require a relational view on consciousness, rather than supporting it.

In his On the Origin of Objects, the computer scientist Brian Cantwell Smith presents his views on the philosophical and metaphysical foundations of computation, artificial intelligence and cognitive science, and offers an argument for the embedded, 'participatory' role of cognition. Cantwell Smith's views are not well known among philosophers and deserve more attention. In my paper, I will try to sketch his answer to the question 'What is Cognition?' The question, according to Cantwell Smith, must be refined as 'What is the Problem Cognition Solves?' I will offer a brief sketch of a world in which cognition is superfluous ('The Gear World') , and a more developed sketch of another world (the actual world) in which cognition solves the problem of Coordination Without Causal Control.

I discuss epistemological and ontological topics concerning artefacts within embodied cognition theories. First, I present the debate on artefact kinds, and argue that artefact essentialism is grounded on the cognitivist view in epistemology and cognitive science. It is subsequently explained that embodied cognition theories provide a better account of kinds and categorisation. They yield an evolutionary account of human cognition, in which categories and artefacts have co-evolved. Artefacts thus obtain a central place in epistemology. The epistemological issues have ontological repercussions for artefacts¹ creator¹s intentions, artefact functions, artefact kinds, and the kind of artefact¹. We conclude that these conclusions are valid for primitive forms of cognition and artefact design as well as for contemporary advanced technological design.

Recently internalists (Adams and Aizawa 2001, 2006 forthcoming and Rupert 2004) have mounted a counter-attack on the attempt to redefine the bounds of cognition. Their counter-arguments are aimed at the extended mind hypothesis which, as Andy Clark has recently put it, is the view that "the material vehicles of cognition can be spread out across brain, body and certain aspects of the physical environment itself." (Clark 2005, 1) However, I think that the extended mind hypothesis is part of a more radical project which I call cognitive integration (Menary 2006), which is the view that internal and external vehicles and processes are integrated into a whole. It is this more radical project that Clark and others are really engaged in. Cognitive integration can be defended against the internalist counter arguments of Adams and Aizawa (henceforth A&A) and Rupert and I shall endeavour to show how.