DEVELOPMENT OF THE MEANINGS OF DUKKHA AND SUKKHA
Since rotary motion was first put into practice, the main problem was to get it running smoothly.
Dukkha described when a wheel was not running smoothly. Sukkha described when it was running smoothly.
Dukkha and Sukkha were not just abstract concepts as they are today in Buddhism, they were very real daily facts of life, they were relevant to all areas of getting practical life running smoothly.
Words like this often get modified and used in different contexts. The word musicians used to 'tune' an instrument, developed to 'tune' in a radio, or get attuned to a situation. The concepts 'turn-on' and 'turn-off' probably come from turning on gas taps. This is a basic fact about how languages develop.
It would be understandable if Dukkha was used for anything which went wrong – in a practical or emotional context, and Sukkha for when it was going well.
When food tasted good it was Sukkha, when the beans burnt it was Dukkha. Sukkha was happiness or contentment, after a good day when everything went well – ahhh Sukkha. Whereas Dukkha was in all probability also used as a swear word.
Then consider how this axle to hub connection is actually a pole through a hole – and Hindus had no great inhibitions about sexuality, we are in the land of the Karma Sutra... so everyone knew that famous chat up line: "How about a bit of Sukkha, honey"; and they had thought to themselves one lonely night: "Dukkha is better than no Kha".
Dukkha was a very common word, and it had a very wide usage as something bad, or wrong before it became central to Buddha's new teaching.
Please continue with Buddha's First Noble Truth