A leaf that falls into a stream (or a leaf we intentionally drop into a stream) just where the water disappears into the ground...will come out again at the next opening, because the underground stream has faithfully carried it there, though during this journey it has been beyond the reach of any outside interference. In the same way, an idea that has been introduced into our minds (or that we ourselves have intentionally introduced) will produce its effects after longer or shorter subconscious development.