Other conditions he had to be aware of were rocks that rolled, or pebbles which were thrownat his fire, or any constant noise, and he then had to walk in the direction in which any ofthese phenomena occurred until the spirit revealed itself.There were many ways in which such a being put a warrior to the test. It might suddenly leapin front of him, in the most horrendous appearance, or it might grab the man from the backand not turn him loose and keep him pinned down for hours. It might also topple a tree onhim. Don Juan said that those were truly dangerous forces, and although they could not kill aman hand to hand, they could cause his death by fright, or by actually letting objects fall onhim, or by appearing suddenly and causing him to stumble, lose his footing, and go over aprecipice.He told me that if I ever found one of those beings under inappropriate circumstances I shouldnever attempt to struggle with it because it would kill me. It would rob my soul. So I shouldthrow myself to the ground and bear it until the morning."When a man is facing the ally, the giver of secrets, he has to muster up all his courage andgrab it before it grabs him, or chase it before it chases him. The chase must be relentless andthen comes the struggle. The man must wrestle the spirit to the ground and keep it there untilit gives him power."I asked him if these forces had substance, if one could really touch them. I said that the veryidea of a "spirit" connoted something ethereal to me."Don't call them spirits," he said. "Call them allies; call them inexplicable forces."He was silent for a while, then he lay on his back and propped his head on his folded arms. Iinsisted on knowing if those beings had substance."You're damn right they have substance," he said after another moment of silence. "When onestruggles with them they are solid, but that feeling lasts only a moment. Those beings rely ona man's fear; therefore if the man struggling with one of them is a warrior, the being loses itstension very quickly while the man becomes more vigorous. One can actually absorb thespirit's tension.""What kind of tension is that?" I asked."Power. When one touches them, they vibrate as if they were ready to rip one apart. But thatis only a show. The tension ends when the man maintains his grip.""What happens when they lose their tension? Do they become like air?""No, they just become flaccid. They still have substance, though. But it is not like anythingone has ever touched."