The following quotes are from:

Carlos Castaneda, A Separate Reality: Further Conversations with Don Juan. Pocket Books 1972. Pp. 146-149.

“‘What exactly is the will? Is it determination, like the determination of your grandson Lucio to have a motorcycle?

            ‘No,’ don Juan said softly and giggled. ‘That’s not will. Lucio only indulges. Will is something else, something very clear and powerful which can direct our acts. Will is something a man uses, for instance, to win a battle which he, by all calculations, should lose.’

            ‘Then will must be what we call courage,’ I said.

            ‘No. Courage is something else. Men of courage are dependable men, noble men perennially surrounded by people who flock around them and admire them; yet very few men of courage have ill. Usually they are fearless men who are given to performing daring common-sense acts; most of the time a courageous man is also fearsome and feared. Will, on the other hand, has to do with astonishing feats that defy our common sense.’

            ‘Is will the control we may have over ourselves?’ I asked.

            ‘You may say that it is a kind of control.’

            ‘Do you think I can exercise my will, for instance, by denying myself certain things?’

            ‘Such as asking questions?’ he interjected.

            He said it in such a mischievous tone that I had to stop writing to look at him. We both laughed.

            ‘No,’ he said. ‘Denying yourself is an indulgence, and I don’t recommend anything of the kind. That is the reason why I let you ask all the questions you want. If I told you to stop asking questions, you might warp your will trying to do that. The indulgence of denying is by far the worst; it forces us to believe we are doing great things, when in effect we are only fixed within ourselves. To stop asking questions is not the will I’m talking about. Will is a power. And since it is a power it has to be controlled and tuned and that takes time. I know that and I’m patient with you. When I was your age I was as impulsive as you. Yet I have changed. Our will operates in spite of our indulgence. For example, your will is already opening your gap, little by little.’

            ‘What gap are you talking about?’

            ‘There is a gap in us; like the sot spot on the head of a child which closes with age, this gap opens as one develops one’s will.’

            ‘Where is that gap?’

            ‘At the place of your luminous fibers,’ he said, pointing to his abdominal area.

            ‘What is it like? What is it for?’

            ‘It’s an opening. It allows a space for the will to shoot out, like an arrow.’

            ‘Is the ill an object? Or like an object?’

            ‘No. I just said that to make you understand. What a sorcerer calls will is a power within ourselves. It is not a thought, or an object, or a wish. To stop asking questions is not will because it needs thinking and wishing. Will is what can make you succeed when your thoughts tell you that you’re defeated. Will is what makes you invulnerable. Will is what sends a sorcerer through a wall; through space; to the moon if he wants.’

            …

            ‘Let’s go to the hills,’ he said abruptly, and stood up.

            On the way he started talking about will again and laughed at my dismay over not being able to take notes.

            He described will as a force which was the true link between men and the world. He was very careful to establish that the world was whatever we perceive in any manner we may choose to perceive. Don Juan maintained that ‘perceiving the world’ entails a process of apprehending whatever presents itself to us. This particular ‘perceiving’ is done with our senses and with our will.

            I asked him if will was a sixth sense. He said it was rather a relation between ourselves and the perceived world.” 146-147