Questions of principle are sometimes regarded as too unpractical to be important, but I suggest that that is certainly not the case in our subject. The range of phenomena that we have to deal with is so broad that, were it to be dealt with wholly at the technological or practical level, we would be defeated by the sheer quantity and complexity of it. The total range can be handled only piecemeal; among the pieces are those homomorphisms of the complex whole that we call “abstract theory” or “general principles.” They alone give the bird’s-eye view that enables us to move about in this vast field without losing our bearings. I propose, then, to attempt such a bird’s-eye survey.

Excerpt: For half a century, threshold has been known to be important in the activities of nerve cell and synapse, but little is known of the general properties that so ubiquitous a feature must impose on the system’s behaviour in the large. Beurle1, in his investigations of the transmission of waves of activity over a conducting not, noticed that a net with threshold would have a marked tendency to be unstable, but his assumptions were complex, and the origin of the instability is not easily identified. Here we propose to show that an instability, similar to his, can readily be traced from a simpler origin.

Excerpt: The capacity of selfreproduction, although omnipresent in the animate world, is tied up with a host of other characteristics of living organisms and cannot claim to be a fundamental principle. I propose to consider as a fundamental principle of living things their capacity to form coalitions. Thus, sexual reproduction appears to be only a particular manifestation of this capacity. What I call a “coalition” is an aggregate of elements which jointly can do things which all of them separately could never achieve.

First of all, I wish to apologize for this somewhat pompous title, but I hope that at the end of my talk you will have forgiven me for having invoked Plato’s esoteric ideas in order to embellish the thoughts behind a few mundane gadgets. Perhaps you will grant me extenuating circumstances if I am going to make a confession at once, namely, that I believe the time has come when one may conceive of a happy marriage between philosophy and hardware. Since most of the functions of the hardware I am going to discuss in their concepts date back to the famous Dialogues, I felt obliged to give the proper reference.