What causes suffering according to the second Noble Truth?

According to the second of the Four Noble Truths, the origin (samudaya) of suffering is craving, known in Pali as tanha (literally "thirst" or "desire").123

This craving manifests as an intense desire for pleasure, for being, or for nonbeing. According to the doctrine of paticca-samuppada (dependent origination), this craving leads to attachment (upadana), which helps perpetuate the cycle of rebirth known as samsara.12

In broader Buddhist texts, the causes of suffering are also understood to stem from negative ethical actions—such as killing, stealing, and lying—and the negative mental states that motivate them, specifically desire, hatred, and ignorance. Ignorance, in this context, refers to a fundamental misconception of reality, such as perceiving permanence where there is impermanence (anicca) or seeing a self where there is no self (anatta). Ultimately, this chain of conditions traces back to ignorance, where each state depends upon and originates from the preceding one.23