Gerald EdelmanGerald Edelman won the Nobel Prize for elucidating the protein structure of antibody molecules in the human immune system. Early theories of immunology argued that antigens invading the body contained information that "instructed" the formation of antibodies. Edelman argued that the immune system contains a very large collection of antibody components, from which the immune system "selects" those which get assembled to form the right antibody. We know today that a large number of random variations also plays a role in the production of an effective antibody. He saw an analogy between the evolution and operation of the immune system and the evolution of the brain. This led Edelman into neuroscience where he developed major theories about connections between neurons (synapses) and made contributions to the philosophy of mind, including a biological theory of consciousness. Edelman's early work on the mechanisms of cell adhesion showed how cell adhesion molecules or CAMs control the fundamental processes by which single cells combine to create the shapes and forms of multicellular organisms. He called this work, which examines the formation of biological information structures, "topobiology." Today we know that CAMs help organize connections across neural synapses between the pre-synaptic cell, which emits neurotransmitters, and the post-synaptic cell, whose thousands of kinds of receptors conduct many different kinds of signals across the cell membrane. When two cells are wired together, they are not limited to a single function. They are called "plastic" because the synapse can transmit many different messages. Edelman was particularly interested in the growth of the central nervous system and brain. He called his theory of neuronal group selection "Neural Darwinism." Neuronal groups are neurons that have been wired together (see Donald Hebb's neuron assemblies. In 1973 Jean-Pierre Changeux had developed a formal model of synapse selection, which was a precursor of "Neural Darwinism." In 1998 Edelman and Changeux edited the important collection of articles for Daedalus magazine later published as the book Brain. Edelman was a reductionist who rejected any form of dualism. He also did not like "computational" models of the mind. With his younger colleague Giulio Tononi, Edelman wrote "A Universe of Consciousness." In the book, Tononi and Edelman claim that many physical (material) systems are conscious. Their theory predicts whether a system is conscious and to what degree it is conscious. It then attempts to explain what particular experience it is having. Tononi calls his work Integrated Information Theory. IIT is a reductionist, deterministic, and causal theory. According to IIT, a system's consciousness is an intrinsic, fundamental property of any physical system. In that respect, IIT resembles panpsychism, a central element in David Chalmers' solution for what he calls the "hard problem of consciousness." Chapter 1 of the book ,Consciousness:Philosophical Paradox or Scientific Object? contains an excellent survey of the sad state in psychology and the philosophy of mind in the 19th and 20th centuries.
In his 1990 book The Remembered Present Edelman proposed that a theory of consciousness should be based on biology. Today we would say biology and neuroscience.He quotes William James on how important such a theory would be.
A genuine understanding of how mental states arise from the structure and function of the brain would be, as William James declared in 1892, ”the scientific achievement before which all past achievements would pale.” Can a comprehensive biological theory of consciousness be constructed in 1990?Perhaps 1990 was not yet the right time, but three decades later, we have a science and a philosophy of biology based on the underlying information structures and processes that give us fundamental explanations for the creation and evolution of everything in the universe. Normal | Teacher | Scholar