In the world we live in, thoughts are lost. They're lost because we don't want to think them. Some thoughts are naughty, some are forbidden, some are undesirable. We don't want to think them. We can't. We don't have time. We're not brave enough. So they're shifted, to places where they're harder to find. Far beyond all the good, allowed, desired, what we're told to do. Then the mind travels. It vanishes for a while. But every traveler comes back one day. Usually with more luggage than they initially took with them.