The sentence "life is suffering", offered as the summary of Buddhism, is wrong twice over: it mistranslates the word and it misstates the claim.
The word is wider than "suffering"
Dukkha does include pain, but its reach is much larger, and the tradition itself divides it three ways:
- Ordinary pain (dukkha-dukkha), physical and mental suffering in the plain sense.
- The suffering of change (viparinama-dukkha), the way pleasant things become sources of distress precisely because they do not last. The pleasure is real; its instability is the problem.
- Conditioned unsatisfactoriness (sankhara-dukkha), a subtle, pervasive inadequacy in all conditioned experience, which can never quite deliver lasting contentment because it is never quite stable.
The third is the one the slogan cannot see. It is not the claim that everything hurts. It is the claim that nothing conditioned can be made to satisfy completely, which is compatible with a great deal of ordinary happiness.
The claim is a diagnosis, not a verdict
Dukkha is the first of four truths, and the structure of the four is the structure of a medical case: a symptom, a cause, a prognosis, a treatment. The second truth gives the cause (craving), the third says the condition can end, and the fourth prescribes the path. A statement that comes packaged with "and here is how it is cured" is not pessimism, and the tradition presses the comparison deliberately, casting the Buddha as a physician rather than a prophet of doom.
Reducing all four truths to the first, and the first to "suffering", keeps the diagnosis and throws away the cure, which is exactly the half the tradition thought was the good news.