One thing I have learned from asking people about their own experience of thinking is that most people have never thought about it - and quite a few seem unable to think about it.
Many people find it very difficult/impossible to introspect, that is, to look within themselves - their own thinking is experienced as a 'black box' process - they feed things into the box, things come out - but they have no idea what goes on inside the box (and perhaps very little interest).
But a couple of interesting answers were:
1. That thinking about a topic was like selecting a video and replaying it - experiencing pictures and sound; and
2. That thinking was like looking-up text - being in a library and reading passages - thinking was primarily in words, and words were then experienced as pictures and sounds
Neither of these experiences much resemble my own - which is neither visual nor auditory, but rather that of trying to grasp simple concepts, a process of 'feeling' around in a medium, or discarding inessentials... trying to get things so simple that I can grasp them whole... Probably something more tactile than visual or auditory.
I would be interested to hear about other people's experiences of thinking, described in this kind of metaphorical way?...