I spot an interesting analogy about question type raised in the book - Six Thinking Hats by Edward de Bono (though this book is not about questioning skills).
Questions are divided into 2 types. There is a fishing question, which is exploratory (like putting bait on a hook but not knowing quite what might turn up). There is a shooting question, which is used to check out a point and which has a direct yes or not answer (like aiming at a bird and hitting or missing).
When I read the above, I think of the difference between facilitators and trainers. I map them into the different questions which facilitators and trainers will ask respectively. The facilitators tend to ask fishing question. As they question, they do not have the answer in their mind at all. Anything can come up. On the other hand, the trainers tend to ask shooting question. They ask questions to convey the training content. They are targeting at something. They may however not simply ask a direct yes or no question like described by de Bono.
Interestingly, the Fishing Question and Shooting Question help to distinguish the facilitator and trainer role.
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