The second thing we can learn is that when we say the glass is empty, we have to ask, "Empty of what?" It's not empty of air. No. It is empty of tea but it is full of air. So, intelligent question to ask is, “Empty of what?” --- Maybe, many answers. But the first answer may be like this: "Empty of a separate existence, or empty of a separate self."
This rose is empty. You can not say, "The rose is empty of sunshine." There is sunshine in it. There is sunshine in the rose. If you remove the sunshine, the rose collapses. There is a cloud in the rose. Without the clouds, it will be no rain and no rose can grow. And if you take the cloud out of the rose, the rose will collapse. There is the earth in the rose. Without the earth, the soil, the minerals, the rose can not be there for you. So, if we continure to look, we see a lot of things in the rose. We can see that the whole cosmos is present in the rose, including our mind, time, space. So, the rose is really full of the cosmos. You can say that the rose is full of the cosmos. We also, our body is full of the cosmos. --- He will say, "Empty of a separate existence". A rose is made only of non-rose elements. Non-rose elements like the sunshine, the soil, the rain...etc. And when non-rose elements come together, a rose manifests. So, the rose is full of everything but is empty of a separate existence. And that is the meaning of emptiness.
So, there is no separate existence. And when we use that kind of concentration in order to look, we discover a lot of things. And that insight liberates us from anger, from frustration, from discrimination. When a father looks at his son, he should be able to see the nature of emptiness of his son. He must see that his son is made of many elements, many non-son elements. Like the rose is made of many non-rose elements. So, the son is made of many non-son elements, including him, for the father is in the son. In fact, it's not so difficult to demonstrate that the son is the continuation of the father. And the father is there in every cell of the son. And the mother, also. The father, mother is non-son element that makes up the son. And if we continue, we see the education, food, culture, everything that can be called non-son element in the son.
And when the son looks at his father, the son can see that the father is made of non-father elements, including the son. If there is no son, how could he be the father? And he can see the father in himself and the father can see himself in the son. Like a teacher and disciple, it is because of the disciple that the teacher is the teacher. There is the teacher that is why the disciple can be the disciple. So, there is a nature of interbeing. This is, because that is. And this is the most simple Buddhist description in the Buddhist scriptures about emptiness, about interbeing. This is, because that is. Extremely simple but extremely important. This is not, because that is not.
And I think the modern sciences are trying to demonstrate that also in terms of a particle, in terms of a quantum. David Bohm said something like one electron is made of by all the other electrons. One contains the many, the all. It's like we said the rose contains the whole cosmos. So, nowadays in the quantum physics, they speak very much the same kind of language.
So, if the father is capable of seeing that his son carries his father within himself, if the father can see that the son is the continuation of the father, the suffering of the son is the suffering of the father and then he goes have that kind of insight called emptiness. Because making his son suffer means making himself suffer. And the son also can practice like that. He knows that his father is in him. They inter-are. They are in each other. And making one suffer means making the other suffer at the same time.
And when you have that concentration, that insight, you will prevent the other person to suffer. Because you know that his suffering is your own suffering. And in Plum Village we used to say that suffering is not an individual matter. And we also say that happiness is not an individual matter. If the father suffers, there is no way that the son can be happy. Vice versa. And that is the door of liberation called emptiness. And practice looking in such a way that concentration called emptiness is present in your way of thinking, of looking, then you are free from discrimination. Discrimination between father and son, Palestinian and the Jews, and so on, north and the south, black and white, Hindus and Muslims. If the other side suffers, you suffer also because you inter-are, you are empty in your own nature. This is the very important teaching and the practice in Buddhism.
Thích Nhất Hạnh