It is a very interesting thing, and you must try to understand what I am saying about momentum. When I make a sudden movement, energy flows in, but when I repeat the movement the momentum no longer takes energy. (He demonstrates.) At the moment when energy has given the initial push, the flow of energy stops and momentum takes over.

Tension needs energy. If tension is absent, less energy is spent. If my arm is tense, as it is now, a continuous current is required, which means that it is connected with the accumulators. If I now move my arm thus, so long as I do it with pauses, I spend energy.

If a man suffers from chronic tension, then, even if he does nothing, even if he is lying down, he uses more energy than a man who spends a whole day in physical labor. But a man who does not have these small chronic tensions certainly wastes no energy when he does not work or move.

Now we must ask ourselves, are there many among us who are free from this terrible disease? Almost all of us--we are not speaking of people in general but of those present, the rest do not concern us--almost all of us have this delightful habit.

We must bear in mind that this energy about which we now speak so simply and easily, which we waste so unnecessarily and involuntarily, this same energy is needed for the work we intend to do and without which we can achieve nothing.

We cannot get more energy, the inflow of energy will not increase: the machine will remain such as it is created. If the machine is made to produce ten amperes it will go on producing ten amperes. The current can be increased only if all the wires and coils are changed. For instance, one coil represents the nose, another a leg, a third a man's complexion or the size of his stomach. So the machine cannot be changed--its structure will remain as it is. The amount of energy produced is constant: even if the machine is put right, this amount will increase very little.

Sit as I sit, close your fists and take care to tighten your muscles only in your fists, as hard as you can. You see, everyone does it differently. One has tightened his legs, another his back.

If you pay attention, you will do it differently from the way you do ordinarily. Learn--when you sit, when you stand, when you lie down--to tense your right arm or your left. (Speaking to M.) Get up, tense your arm and keep the rest of your body relaxed. Try it in practice to understand better. When you pull, try to distinguish strain from resistance.

I now walk without tension, taking care only to keep my balance. If I stand still, I shall rock. Now I want to walk without spending any force. I only give an initial push, the rest goes by momentum. In this way I cross the room without having wasted any force. To do this you must let the movement do itself; it does not depend on you. I said earlier to someone that if he regulates his speed it shows that he is tensing his muscles.

Try to relax everything except your legs, and walk. Pay particular attention to keeping your body passive, but the head and face must be alive. The tongue and eyes must speak.

All day long, at every step, we are annoyed at something, like something, hate something, and so on. Now we are consciously relaxing some parts of our body and consciously tensing others. As we practice it, we do so with enjoyment. Each of us is able to do it more or less, and each one is sure that the more he practices it, the better he will be able to do it. All you need is practice; you must only want to and do it. The desire brings the possibility. I am speaking of physical things.

From tomorrow on, let each person also begin to practice the following exercise: if you are touched to the quick, see that it does not spread all over the body. Control your reaction; do not let it spread.