This, as the Twelve Links, is an explicit statement of causation in Buddhism. In its most general form, it is:
"When this is, that is. With the arising of this, that arises.
When this is not, that is not. With the cessation of this, that ceases." Gotama, MN 115. Bahudhatuka Sutta
That is, it is about causation
The twelve links are derived from the Noble Truths.
Gotama obtained the list by asking, "What is necessary for suffering to persist?", or, "On what does suffering depend?" In the present time stillness of deep meditation, Gotama observed that birth (manifestation) was necessary for suffering.
That is, an identity must exist for suffering to occur. (Suffering, here, is what I called suffering by definition − it might be a good feeling for a while.) For instance, "I am sad". To be sad, I need an identity, that of a sad person. Similarly, "I am ecstatic" depends on the identity of an ecstatic person. Both these examples are examples of suffering because they are changes (growing and aging), and they both come to an end (death). (Neither is permanent.) If an entity did not exist, there would be no suffering (See Monkey Pie).
Gotama observed that if this identity had not appeared (been born, come into existence), then suffering would not occur. If I didn't appear as an ecstatic person, then I wouldn't lament the change back to normal. Similarly, if I didn't appear as a sad person, then I wouldn't be sad. In both cases our present serenity and joy (or lack of it) is disturbed, increasing suffering.
Now he continued, seeking the origin of birth. The origin of birth is becoming. When an identity appears, whether a baby or a personality, it appears already formed (to some degree). The process of entering this identity is called becoming. For instance, a baby does not appear from nothing. There is the process of becoming where the baby is formed from the sperm and oven and various changes to produce a baby.
In a worldly sense, when we are preparing for a challenging interview, we assemble our mental and physical props. We mentally prepare for questions and answers. We also assemble the physical things, such as combing our hair, and putting on our best clothes. We go to the interview and become an interviewee (birth of that identity).
Becoming depends on clinging or attachment. Clinging means holding on (as a flame clings to the burning wood).
In sense-pleasure clinging we are attracted to a sight, sound, etc, like a donkey to a carrot. We can't stop looking, etc, at the object. We can cling to mental images, etc. When we cling to thoughts (good and bad) we can't get them out of our minds. We seem stuck to them. This is obsessive clinging.
Sometimes we cling to wrong views. These can be wrong views about the nature of life which produce suffering. They include believing that, or acting as if, this experience will last forever, when it is impermanent.
Rights and rituals clinging is the belief and action of doing things because we think we must. This includes religious practice. In Buddhism, we might be too concerned with doing something exactly to book. At first, this might be helpful, though. Beginners in any subject or practice have to start somewhere and follow instructions. But later this clinging should be avoided. It is different from doing something for a good reason (to reduce suffering). This type of clinging is like a compulsion.
Self-doctrine clinging is particularly Buddhist. It is clinging to a theory of self, believing in me and mine. At the higher levels of Buddhist practice, it is clinging to a subtle belief in self, which is one of the final fetters to overcome.
Clinging depends on craving. That is wanting what we have to go away. For instance, wanting an irksome task to go away, or wanting someone else to do it. Craving is also wanting what we don't have. For instance craving a new car. When we crave a new car, we have thoughts and images and feelings of a new car. We become attached to the idea of a new car. These thoughts, becoming part of us. And we start reading ads and being alert to the possibility of getting a new car. That is, we become a 'car buyer'. (Previously, we may have shown little interest in cars, but now we have a new identity (birth) as a car sales prospect.
Craving depends on feeling. Without feeling, we wouldn't be attracted to something, averse to it, or neutral towards it. (craving). For instance, a man might see an impressive suit (a pleasant feeling based on sight-contact). And so he craves it. If he didn't find it a pleasant idea, he wouldn't crave it. A woman might look in the mirror and think, "My hair's a mess", and want to change it.
In the above example, if the eye didn't make contact with the object of desire, then desire would not have arisen.
Clearly, we make sense-media contact by seeing, hearing, smelling, tasting or touching something. Or mind-contact by thinking about it. For example, a man sees a suit, that is, the eye media makes contact with it (figuratively, his eyes land on it). Dependent on this, he craves it. If he didn't have a good feeling, he wouldn't crave it.
Dependent on this craving, he imagines himself wearing the suit and imagines others admiring him (clinging to mental images). That is, he becomes attached to it (his mind is filled with thoughts, images and feelings relating to this suit). In this way, he creates what is necessary to become a suit buyer. So, dependent on this attachment, he becomes an identity of someone who is a suit-buyer, or an identity of an impressive person wearing that suit (birth). He is a different person. He goes over to the suit feels it, tries it on, and pays for it.
In this new identity, he goes out in his suit, delighted when others admire it, and treat him as an important person. Or becoming angry when they don't, or when he or they spill something on it. Of course, this identity ages (as does the suit) and after a time, the delight no longer exists (death). The cycle may repeat when he eyes something else.
Sometimes the aging and death of the identity occur slowly, so we are aware only of a general dissatisfaction. A nasty aftertaste. We may be unaware why we are unhappy.
Sometimes, however, this aging and death of the identity happens quickly. As a boy I had a new jacket (which I liked, perhaps one of my heroes wore a similar jacket). But on the first day I wore it, I tore it to shreds (death of the identity) crawling through a barbed wire fence! In this case, the suffering came quickly and painfully!
Contact depends on the six sense media. They are the eye, ear, nose, tongue, body, and mind.
The above is based on the work of Thanissaro Bhikkhu: "The Shape of Suffering A Study of Dependent Co-arising"