"When in doubt, black out," meant simply that if a situation arose which seemed impossible to handle rationally, the enhosted Learner's last resort was reliance upon the instinctive behavior of the host. The only thing to be done was to pull the mind into a tiny knot bobbing in the host's own brain, and let the host itself, once more in control, take the Learner instinctively to environmental victory. Or defeat.
There were dangers, of course. A Learner enhosted in a chicken, for instance, would be a fool to trust the chicken's instincts regarding, say, a snake. A chicken confronted by a snake tends to become hypnotized by its deadly adversary, and to stand stupidly in place until it is killed. In cases of that sort, the Learner would be safer taking control and going clucking off to the nearest high ground.
On the other hand, a Learner inhabiting something with the hairtrigger instincts of a bat would be much better off letting the animal's instincts take over in moments of grave risk, such as flying through the blades of a revolving fan. A bat could get through without a second thought about those whirling metal scythes, but a man's mind could not think fast enough to avoid a grim death by all-over amputation.
"Maybe," Jerry thought hopefully, "I've got an easy one." It was possible, of course. His host might be in the midst of an afternoon siesta, and Jerry could relax and "sit out" his forty minutes of Contact. But such cases were few. At any moment a predator might come down into that orifice in the soil, and Jerry would have to fight for his host's life to preserve his own. Relaxed Learning was seldom feasible.
"I'd better see what sort of fighting equipment I have," he decided, wishing vainly that he could just turn his head and look his body over. This proceeding by feel was a slow, tortuous, and sometimes deceptive process. Hollow fangs that seemed capable of injecting venom into an enemy might—as in the case of the Venusian Sea Vampires—turn out to be an organ for drinking water, the sacs above the fangs being for digesting liquids and not for storing poisons.
Jerry stimulated what should be his tongue into action, checking for the presence of fangs. Within the mouth of the creature, which felt large in relation to its head, he sensed a rasping movement, a kind of dull dry rustling, but could feel nothing with the tongue itself. "Best have a look at it," he decided suddenly, and, opening his jaws, extended the tongue.
Jerry was distinctly shocked by the thing that skewed and writhed forward from beneath his eyes. His sensation was not unlike that of a man who opens his mouth and finds a snake in it. And Jerry further realized that he was now seeing with another sextet of eyes, at the end of the tongue.
He was not one alien—he was two!