In Buddhism, the three marks of existence are three characteristics (Pali: tilakkhaṇa; Sanskrit: त्रिलक्षण, trilakṣaṇa) of all existence and beings, namely impermanence (aniccā), non-self (anattā) and unsatisfactoriness or suffering (duḥkha). These three characteristics are mentioned in verses 277, 278 and 279 of the Dhammapada. That humans are subject to delusion about the three marks, that this delusion results in suffering, and that removal of that delusion results in the end of suffering, is a central theme in the Buddhist Four Noble Truths and Noble Eightfold Path.
According to Thich Nhat Hanh, the three seals are impermanence, non-self and nirvana. He says in "The heart of the Buddha's Teaching" that "In several sutras the Buddha taught that nirvana, the joy of completely extinguishing our ideas and concepts, rather than suffering, is one of the Three Dharma Seals."
Philologist Christopher Beckwith has identified the three terms used here by Pyrrho - adiaphora, astathmēta, and anepikrita - to be nearly direct translations of anatta, dukkha, and anicca into ancient Greek.