I was perusing the site, and I came up with this weird thought: Can a person think about the thought that they are thinking? Because at first I thought no... but then I thought by posing this question I was thinking about what I was thinking... but I started to doubt my thoughts... so I thought it might be a good idea to get a second opinion.

Yes, because we can think about our own mental states. Thus I may be thinking about espresso machines, and then wonder why I am doing that. The first thought is about those machines; the second thought is about the first thought. Desires may also stack up in this way. Thus I may desire a new espresso machine, but also wish that I didn't have that desire (say because its immature: I already have a perfectly good espresso machine).

Might the question have concerned self-referring thoughts? Viz: Is it possible for me now to think about the very thought I am now thinking?

But, if you think about it, I just did. So it is.

I can do it again: I think that the very thought I am now having is a true one. Is it?

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