D. S. Halacy defines "cyborg" as a man who uses machines to increase his power; cyborg was born when humans began to make tools, no matter how primitive. Cyborg applies equally well to a laborer using an ordinary shovel and to an investigator handling radioactive material by manipulating giant pincers. The term even includes people with pacemakers, nylon blood vessels, and reinforced bones. The author does not limit himself only to surgery; he also writes about psychic drugs, myo-electric control, hypothermia, tissue culture, and space medicine.