To make psychology into experimental epistemology is to attempt to understand the embodiment of mind. Here we are confronted by what seem to be three… - Warren Sturgis McCulloch

We suppose that some axonal terminations cannot at first excite the succeeding neuron; but if at any time the neuron fires, and the axonal terminations are simultaneously excited, they become synapses of the ordinary kind, henceforth capable of exciting the neuron. The loss of an inhibitory synapse gives an entirely equivalent result.

This book is not for the engineer content with hardware, nor for the biologist uneasy outside his specialty; for it depicts that miscegenation of Art and Science which begets inanimate objects that behave like living systems. They regulate themselves and survive: They adapt and they compute: They invent. They co-operate and they compete. Naturally they evolve rapidly.
Pure mathematics, being mere tautology, and pure physics, being mere fact, could not have engendered them; for creatures to live, must sense the useful and the good; and engines to run must have energy available as work : and both, to endure, must regulate themselves. So it is to Thermodynamics and to its brother Σp log p, called Information Theory, that we look for the distinctions between work and energy and between signal and noise.
For like cause we look to reflexology and its brother feedback, christened Multiple Closed Loop Servo Theory, for mechanical explanation of Entelechy in Homeostasis and in appetition. This is that governance, whether in living creatures and their societies or in our living artefacts, that is now called Cybernetics.

Don't bite my finger, look where I am pointing.