An explanatory gap exists between physics and experience, raising the hard problem of consciousness: why are certain physical systems associated with an experience of an external world from an internal perspective? The living mirror theory holds that consciousness can be understood as arising from the computational interaction between a living system and its environment that is required for the organism's existence and survival. Maintaining a boundary that protects the system against destructive forces requires an interaction between the organism and its (...) outside world that can be cast in terms of Bayesian inference. The living mirror theory holds that this computational interaction results in statistical properties of the material world that are, in the absence of life, only implicit, becoming explicit in informational terms. This is held to give rise to the beliefs in qualities that constitute consciousness. Consciousness is therefore a necessary feature of all living systems as, in a world governed by the second law of thermodynamics, survival depends on the construction of beliefs regarding the potentially destructive forces in the outside world. From this perspective, consciousness is shown to be not a property of the brain in particular but instead to be a necessary feature of the life process itself. (shrink)

The idea that concentration gradients of crucial substances might control the pattern of development, even in the embryos of complex organisms, has been around for a long time, but mostly in obscure forms. Twenty five years ago clear, experimentally testable ideas about how such gradients might work were enunciated, and more recently the morphogen gradient principle was shown to underlie the beginnings of patterning in Drosophila. Is it also central to vertebrate development? Four recent papers raise experimentation to a new (...) level(1–4), while showing how difficult it might be to pin down the precise form of the mechanism. (shrink)

In the last few years, an understanding has emerged of the developmental mechanism for the consistent internal left–right structure, termed situs, that characterises vertebrate anatomy. This involves largely vertebrate‐conserved (i.e. ‘phylotypic’) gene expression cascades that encode ‘leftness’ and ‘rightness’ in appropriate tissues either side of the embryo's midline soon after gastrulation. Recent evidence indicates that the initial, directional symmetry breaking that initiates these cascades utilises mechanisms that are conserved or at least closely related in different vertebrate types. I describe a (...) scenario whereby the capacity for directional modification of an otherwise bilateral body plan can be viewed as an adaptive innovation rather closely connected with vertebrate origins, enabling optimal ‘design’ for very active lifestyles. But an alternative scenario, while retaining the view that situs and indeed other vertebrate functional lateralisations are deeply adaptive, proposes that they originated in the co‐optation of left–right developmental information inherited from a very early stage in metazoan diversification. It is proposed that a remote chordate ancestor lost its original or ‘ur‐bilaterian’ symmetry to pass through an altogether non‐symmetrical stage, and that the vertebrate dorsoventral midline plane is not descended from that original one. I review the considerable evidence in favour of this scenario, and discuss its wider implications for directional asymmetries across the Metazoa. BioEssays 26:413–421, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

This paper posits that the writings of Hélène Cixous convey a remarkable intimacy, firstly in the representation of love, with its relationship to knowledge and time; and, secondly, in the relationship her texts create with the reader. Cixous’s use of her life, from the publication of her dreams to the life events which are the creative impetus for texts such as The Book of Promethea and The Day I Wasn’t There inform a discussion of the figures of the lover, the (...) dead child, and that of the brother, his interdiction against appearing in her texts, and the ethical dimension this produces for the reader. Finally, the implications of Cixous’s imbrication of literature, dreaming, writing and life is considered as a gesture of intimacy which opens a possibility for radically reconceiving our usual separation of these realms of experience. (shrink)