If you’re practising a headstand.

If, while you are practising a headstand, your teacher gives you advice.

Even if it’s advice you are in complete agreement with. Even if it is advice that sets off little lights of understanding blinking and flashing all over your mind. Even if you feel the utmost need to express your sudden understanding and complete agreement with the advice.

Even if all this applies, remember that you are practising a headstand.

Do not nod.