The problem of how mental processes arise from purely physical ones has puzzled philosophers from at least the time of Aristotle. Recent major advances in neuroscience have enabled philosophers to phrase their hypotheses in precise biological terms, but are they any closer to explaining consciousness? This book contains contributions from philosophers representing several schools of thought. Some believe that although at present we have no concept of what the neurophysiological basis of consciousness might be, ultimately, consciousness will be explicable in terms of patterns of neuronal firing within the brain. Others deny this, and maintain that however much we learn about how the brain works, consciousness will remain unexplained.