Four experiments assessed the relative involvement of different working memory components in two types of reasoning tasks: propositional and spatial reasoning. Using the secondary-task methodology, visual, central-executive, and phonological loads were realised. Although the involvement of visuospatial resources in propositional reasoning has traditionally been considered to be small, an overall analysis of the present data suggests an alternative account. A theoretical analysis of the pattern of results in terms of Evans' (1984, 1989) twostage theory of reasoning is proposed and tested (...) in Experiments 3 and 4, in which direct evidence for the alternative account was obtained: significant disruption of propositional reasoning by a concurrent spatial load. (shrink)

This dissertation defends the reliability of first-person methods for studying consciousness, and applies first-person experiments to two philosophical problems: the experience of size and of the self. In chapter 1, I discuss the motivations for taking a first-person approach to consciousness, the background assumptions of the dissertation and some methodological preliminaries. In chapter 2, I address the claim that phenomenal judgements are far less reliable than perceptual judgements (Schwitzgebel, 2011). I argue that the main errors and limitations in making phenomenal (...) judgements are due to domain-general factors, which are shared in the formation of perceptual judgements. Phenomenal judgements may still be statistically less reliable than perceptual judgements, though I provide reasons for thinking that Schwitzgebel (2011) overstates the case for statistical unreliability. I also provide criteria for distinguishing between reliable and unreliable phenomenal judgements, hence defending phenomenal judgements against general introspective scepticism. Having identified the main errors in making phenomenal judgements, in chapter 3, I discuss how first-person experiments can be used to control for these errors. I provide examples, and discuss how they overcome attentional and conceptual errors, minimise biases, and exhibit high intersubjective reliability. In chapter 4, I investigate size experience. I use first-person experiments and empirical findings to argue that distant things looking smaller cannot be explained as an awareness of instantiated objective properties (visual angle or retinal image size). I also discuss how an awareness of uninstantiated objective properties cannot adequately account for the phenomenal character of size experience. This provides support for a subjectivist account of variance in size experience. In chapter 5, I investigate the sense of self. I distinguish between a weak sense of self (for-me-ness) and a strong sense of self in which there is a polarity between subject and object. I use first-person experiments from Douglas Harding to demonstrate an explicit strong sense of self, specifically when I point at where others see my face. I also argue that this sense of self is not explained by inference, thoughts, feelings, imagination nor the viewpoint. Rather, it is part of the structure of experience that I seem to be looking from here. Even if there is a sense of self, there may be no self. The question of chapter 6 is whether there can be a direct experience of the self. I argue that to function as a bearer of experience the subject must be single and lack sensory qualities in itself. I use Harding’s first-person experiments to investigate the visual gap where I cannot see my head. I argue that it conforms to the above criteria, and hence is a candidate for being the subject. This finding, in conjunction with the fact that I seem to be looking from the same location, provides prima facie evidence for the reality of the subject. I hold then that contrary to Hume and most philosophers since, that there can be a direct self-experience, if one knows which direction to attend. (shrink)