Sit quietly for two minutes and watch what happens. Thoughts arrive. Nobody summoned any of them and nobody can predict the next one. Try to guess what will be thought in four seconds and it simply cannot be done, which is a strange situation to be in with regard to one's own mind and one we almost never remark on.
Most of them can be traced if anybody is willing to look. Something was said this morning, something is unfinished, something has been circling for weeks and is coming round again. Ordinary business from ordinary sources, and nothing mysterious in any of it once the thread is followed back.
But not all of them. Some arrive with no route in at all. They are not about anything current, they connect to nothing that has happened recently, and they are frequently more useful than everything the mind produced deliberately all week. There is no explanation for those, and the question is not a naive one however often it is dismissed.
Two kinds
The difference between the two is not subtlety, it is texture, and once it is noticed it cannot be unnoticed. An assembled thought comes with its working attached. The steps can be seen, the route is known, and it feels like something done rather than something that happened.
The other kind arrives whole. There is no sensation of construction at any point. It is simply there, complete, often at a moment when nothing in particular was being done and the attention was somewhere else entirely. It does not feel like something made. It feels like something received, and the difference in feeling is quite distinct.
People notice this most in the shower, on a walk, in the minute before sleep, in the middle of a long drive. All of those have one feature in common, which is that the mind was not working at the time. It had been let alone for once. And the moment it stopped producing, something else got through.
The question underneath
If we made the thought, why did we not know it before we had it? That is the whole difficulty in a single sentence, and nobody has ever offered a satisfying answer to it.
The reasonable reply is that the mind works below awareness, assembling quietly in the background, and delivers the finished result when it is ready, so the surprise is only about timing rather than about origin. That is probably true for a great many of them, perhaps most. It does not seem to cover all of them. Some carry information that was never had, and some concern a thing never once considered.
Perhaps the whole distinction is an illusion produced by not being able to see our own machinery. That is entirely possible and should be held as likely. But the question makes people uncomfortable, and they change the subject rather quickly, and discomfort at a question is usually a sign that the question is a real one rather than a silly one.
Why it matters at all
It matters because of what we do with the arriving kind. Almost always, we dismiss them. They do not come with credentials attached. They cannot be justified in a meeting or defended to anybody. They have no working to show, and we have been trained since childhood to show our working before anything is accepted.
So the thought arrives, and something in us knows immediately that it is important, and then the mind arrives half a second later and asks where it came from and on what basis. Having no answer to either question, it gets set aside and the day goes on. This happens hundreds of times over the years, and after enough of it they may well stop coming, or keep coming to somebody who has entirely stopped noticing.
Some people write them down. Not to act on them, and not to trust them automatically, which would be its own kind of foolishness. Simply to give them somewhere to exist for longer than four seconds. Most turn out to be nothing much when they are looked at again later. A small number change the direction of years, and there is no telling which is which at the moment of arrival, and there probably never will be.