The traditional Buddhist belief that all happiness must in the end change into unhappiness is not a cheerful one. It need never be taken too literally as being universally true, nor by itself alone, for there are counterweighting truths. When Buddha brought to an end the meditation which culminated in final enlightenment, dawn was just breaking. The last star which vanished with the night and the first one which he saw as he raised his head was Venus. What was his inner state, then? Did it synchronize with the reputed planetary influence of Venus--joyous and happy felicity--or with the gloomy view of life which tradition later associated with Buddhism? Who that has had a glimpse of those higher states, felt their serenity, can doubt it was the first? The Overself is not subjected to suffering. But this is not to say that it is bubbling with happiness. It is rather like an immensely deep ocean, perfectly tranquil below the surface. That tranquillity is its ever-present condition and is a true joyousness which ordinary people rarely know. This is what Buddha felt. This is what he called NIRVANA.
-- Notebooks Category 23: Advanced Contemplation > Chapter 8 : The Void As Contemplative Experience > # 203
-- Perspectives > Chapter 23: Advanced Contemplation > # 61