The general problem of visual search can be shown to be computationally intractable in a formal, complexity-theoretic sense, yet visual search is extensively involved in everyday perception, and biological systems manage to perform it remarkably well. Complexity level analysis may resolve this contradiction. Visual search can be reshaped into tractability through approximations and by optimizing the resources devoted to visual processing. Architectural constraints can be derived using the minimum cost principle to rule out a large class of potential solutions. The (...) evidence speaks strongly against bottom-up approaches to vision. In particular, the constraints suggest an attentional mechanism that exploits knowledge of the specific problem being solved. This analysis of visual search performance in terms of attentional influences on visual information processing and complexity satisfaction allows a large body of neurophysiological and psychological evidence to be tied together. (shrink)

Three big philosophical problems about consciousness are: Why does it exist? How do we explain and understand it? How can we explain brain-consciousness correlations? If functionalism were true, all three problems would be solved. But it is false, and that means all three problems remain unsolved (in that there is no other obvious candidate for a solution). Here, it is argued that the first problem cannot have a solution; this is inherent in the nature of explanation. The second problem is (...) solved by recognizing that (a) there is an explanation as to why science cannot explain consciousness, and (b) consciousness can be explained by a different kind of explanation, empathic or “personalistic” explanation, compatible with, but not reducible to, scientific explanation. The third problem is solved by exploiting David Chalmers“principle of structural coherence”, and involves postulating that sensations experienced by us–visual, auditory, tactile, and so on–amount to minute scattered regions in a vast, multi dimensional “space” of all possible sensations, which vary smoothly, and in a linear way, throughout the space. There is also the space of all possible sentient brain processes. There is just one, unique one-one mapping between these two spaces that preserves continuity and linearity. It is this which provides the explanation as to why brain processes and sensations are correlated as they are. I consider objections to this unique-matching theory, and consider how the theory might be empirically confirmed. (shrink)

The Urgent Need for an Intellectual Revolution For much of my working life (from 1972 onwards) I have argued, in and out of print, that we need to bring about a revolution in the aims and methods of science – and of academic inquiry more generally. Instead of giving priority to the search for knowledge, academia needs to devote itself to seeking and promoting wisdom by rational means, wisdom being the capacity to realize what is of value in life, for (...) oneself and others, wisdom thus including knowledge, understanding and technological know-how, but much else besides. A basic task ought to be to help humanity learn how to create a better world. (shrink)

1. The Urgent Need for an Intellectual Revolution 2. Two Fundamental Problems 3. Autobiographical Remarks 4. What Kind of Inquiry Can Best Help Life of Value to Flourish? 5. How is Life of Value Possible in the Physical Universe? 6. Connections between the Two Problems .