²⁰This is from a fundamental discourse by the Buddha found in one of the earliest known layers of Buddhist literature, the Pali Canon. Different versions are available in Samyutta Nikaya 56.11, Majjhima Nikaya 141, and Digha Nikaya 22, where the last one is the most detailed version. This quote is part of the description of what is called the Four Noble Truths, of which we here consider only the first one (see footnote 29 in Chapter 14 for the rest). The whole description of the first truth, synthetizing the different versions, says approximately: Birth is suffering, ageing is suffering, illness is suffering, death is suffering; grief, lamentation, pain, distress, and despair are suffering; union with what is displeasing is suffering, separation from what is pleasing is suffering, not to get what one wants is suffering. (Several partial translations of the Pali Canon are available on the internet and I will often select the translation I find the most compatible with my terminology; the one in the main text here is by Bhikkhu Boddhi.)