What's the difference between desire (chanda) and craving (tanha)? From my understanding, tanha is always unwholesome but chanda can be wholesome or unwholesome.
I have one question, though: is chanda always a kind of "wishful thinking"? Because, based on the other excellent answers, it seems the Buddha used chanda to indicate a neutral (ethically/kammically speaking) kind of desire, with tanha being like a kind of kammically charged chanda. Although, I may be misunderstanding something.
This is a powerful clarification. It suggests that a practitioner experiencing "dryness" or apathy (loss of Chanda) has actually drifted away from the Sutta instructions for Jhana/Samadhi, rather than succeeding in "letting go." The distinction between abandoning Tanha but cultivating Chanda seems vital for preventing the "spiritual depression" often reported by isolated meditators.
Here, chanda is clearly a word for right effort (sammā vāyāma). The Commentaries regard this as a wholesome desire (kusala-c,chanda), a spiritual desire (or Dharma-moved desire, dhamma-c,chanda), the desire (or will) to create wholesome states. Assuming it's 'positive' chanda that you want to develop, I think the above suggests several answers:
Chanda is a reason for Tanha. Ignorance (Avidya) is the cause for Chanda means it's the cause for Tanha. Then Tanha causes to increases the Chanda 's density towards something. Nirvana is understanding Chanda towards something is a useless thing. As nothing in this world is going to satisfy the intention (Chanda) the living beings have. That's why no one can reach ultimate satisfaction. If ...
Chanda can be used in two different ways. In “kämachanda”, it is mind blinded by käma or sense pleasures. So it is like Tanha. In this case “Chanda” wrapping one’s mind with samma vaca, samma kammanta, and samma ajiva. As you are Sinhalese, this is the ‘nirukthi’ of the word: (cha + anda, where “cha” is mind and “anda” is “anduma” or clothes).