Allan Kardec. The book of spirits (№ 396701)

We incorrectly imagine that the action of the spirits must be bound by extraordinary phenomena, But this does not happen, the intervention of their unknown to us, and everything that is done with their cooperation, it seems natural, for example, two people can meet under the inspiration of the spirits, meanwhile, this meeting will seem accidental; they were able to convince the man thought to pass by such a place; unable to draw his attention to this subject, if it helps to lead to the desired result.