All of us are born to Nature. Yes, of course we were each born to parents but, if you ask a mother and a father how they did it (besides the obvious), none would be able to tell you how. Since our individual creation is a complete mystery, it makes sense to be respectful of mystery when you approach Acting. The most mysterious of all things in life are our Emotions.
We are all born with our emotions intact; and then their degradation occurs over time. People often become completely numb or the opposite, uncontrollably emotional — the walking wounded. In Acting, we seek to have balanced emotions which then become the springboard for becoming another person. Your emotional equanimity is what allows you to take on the emotional reality of the character. Emotional imbalance is particularly an attribute of Western civilization, which considers emotions to be generally trivial in life, and so we watch them portrayed onscreen. As Westerners, we choose instead to have disease as our most common emotional expression.
When people come to acting class, usually their affections have been turned off to some extent. This is because at different points of pain in your life you decided to restrain your feelings because you were not able to fathom or process those feelings at the time. Acting becomes the best way to give vent to these latent or stuffed sentiments. These pockets of emotion, if never unleashed, will eventually become pernicious.
Each emotion is a form of physical energy in your body, intended as a mode of expression, to communicate with yourself and others. The symptoms of locking them up in a cell are either dull lifelessness or uncontrollable nervousness and explosiveness. In essence, even if the emotions are killed, they seep up through the cracks inappropriately and escape as extreme or uncontrollable innervation, or on the passive side, disease.
The Actor must breathe into their emotions, not stuff or deny them, nor kill them with drugs and alcohol. Yogic breathing is far and away the best resource for emotional balance. In addition, the Actor must seek to understand the roots of upset, malady, or any variance from natural joy as it applies to their own life. Then, in the execution of Acting, emotion occurs Naturally through the imagination and representing that the unseen is real and that the character is themselves. From his vantage point of neutrality, the Actor can immediately dwell on any emotional reality that is implied in the script, and therefore become the character by living in his body and in his world.