Beginning from the scientist-philosopher Michael Polanyi's theory of tacit knowing, and drawing upon a remarkably original model of the mind and its workings, Edward Moss develops the thesis that all consciousness is grammatically structured. Comparison is made in detail with the theories of Daniel Dennett, based on the computer analogy, and with the neurophysiological theories of Gerald Edelman. It is suggested that Moss's top-down psychological model can be integrated with Edelman's bottom-up analysis. Two final chapters explore the philosophical implications of this discussion.