It is not by accident or God’s will that one is born a human or an animal. There is always a cause. Such cause is the origin of suffering, and suffering itself is the effect of samsara.

What does the word “truth” represent, as in the Four Noble Truths? It means reality. Does it mean that samsara is a reality? No, it doesn’t. Here, “truth” represents the condition as perceived by the sages. The difference between what ordinary people perceive and that of the sages is as wide apart as earth and heaven. Ordinary people obscured by ignorance see only the illusions of reality while the sages perceive the true reality. Therefore, the word “truth” is never meant to define the view of ordinary people.

- Quote from The Right View, "The Four Noble Truths—the Path Out of Samsara"