Duḥkha (; Sanskrit:दुःख; Pāli; : dukkha) is an important Buddhist concept, commonly translated as "suffering", "pain", "unsatisfactoriness" or "stress". It refers to the fundamental unsatisfactoriness and painfulness of mundane life. It is the first of the Four Noble Truths and it is one of the three marks of existence. The term is also found in scriptures of Hinduism, such as the Upanishads, in discussions of moksha (spiritual liberation).
Duḥkha (Sanskrit; Pali dukkha) is a term found in ancient Indian literature, meaning anything that is "uneasy, uncomfortable, unpleasant, difficult, causing pain or sadness". It is also a concept in Indian religions about the nature of life that innately includes the "unpleasant", "suffering", "pain", "sorrow", "distress", "grief" or "misery." The term duḥkha does not have a one word English translation, and embodies diverse aspects of unpleasant human experiences. It is opposed to the word sukha, meaning "happiness," "comfort" or "ease."
The word is commonly explained as a derivation from Aryan terminology for an axle hole, referring to an axle hole which is not in the center and leads to a bumpy, uncomfortable ride. According to Winthrop Sargeant,
The ancient Aryans who brought the Sanskrit language to India were a nomadic, horse- and cattle-breeding people who travelled in horse- or ox-drawn vehicles. Su and dus are prefixes indicating good or bad. The word kha, in later Sanskrit meaning "sky," "ether," or "space," was originally the word for "hole," particularly an axle hole of one of the Aryan's vehicles. Thus sukha … meant, originally, "having a good axle hole," while duhkha meant "having a poor axle hole," leading to discomfort.
The word dukkha is made up of the prefix du and the root kha. Du means “bad” or “difficult.” Kha means “empty.” “Empty,” here, refers to several things—some specific, others more general. One of the specific meanings refers to the empty axle hole of a wheel. If the axle fits badly into the center hole, we get a very bumpy ride. This is a good analogy for our ride through saṃsāra.
However, according to Monier Monier-Williams, the actual roots of the Pali term dukkha appear to be Sanskrit दुस्- (dus-, "bad") + स्था (stha, "to stand"). Regular phonological changes in the development of Sanskrit into the various Prakrits led to a shift from dus-sthā to duḥkha to dukkha.
Contemporary translators of Buddhist texts use a variety of English words to convey the aspects of duḥkha. Early Western translators of Buddhist texts (before the 1970s) typically translated the Pali term dukkha as "suffering." Later translators have emphasized that "suffering" is too limited a translation for the term duḥkha, and have preferred to either leave the term untranslated or to clarify that translation with terms such as anxiety, distress, frustration, unease, unsatisfactoriness, etc. Many contemporary teachers, scholars, and translators have used the term "unsatisfactoriness" to emphasize the subtlest aspects of dukkha. Contemporary translators have used a variety of English words to translate the term duḥkha,[note 1] and many translators prefer to leave the term untranslated.
The Buddhist tradition emphasizes the importance of developing insight into the nature of duḥkha, the conditions that cause it, and how it can be overcome. This process is formulated in the teachings on the Four Noble Truths.
In Hindu literature, the earliest Upaniṣads — the Bṛhadāraṇyaka and the Chāndogya — in all likelihood predate the advent of Buddhism.[note 3] In these scriptures of Hinduism, the Sanskrit word duḥkha (दुःख) appears in the sense of "suffering, sorrow, distress", and in the context of a spiritual pursuit and liberation through the knowledge of Atman (soul/self).
The concept of sorrow and suffering, and self-knowledge as a means to overcome it, appears extensively with other terms in the pre-Buddhist Upanishads. The term Duhkha also appears in many other middle and later post-Buddhist Upanishads such as the verse 6.20 of Shvetashvatara Upanishad, as well as in the Bhagavada Gita, all in the context of moksha.[note 6] The term also appears in the foundational Sutras of the six schools of Hindu philosophy, such as the opening lines of Samkhya karika of the Samkhya school.
Both Hinduism and Buddhism emphasize that one overcomes duḥkha through the development of understanding.[note 7] However, the two religions widely differ in the nature of that understanding. Hinduism emphasizes the understanding and acceptance of Atman (self, soul) and Brahman, while Buddhism emphasizes the understanding and acceptance of Anatta (Anatman, non-self, non-soul) as each discusses the means to liberation from Duḥkha.