It means that if dreams give us insight, some of us can see something happen in a dream, that when it happens in real life it feels like De-ja-vu. Dreams can have scenarios that make us frightened of the guy who usually gets off at the same bus stop as you, and walk a short while behind you before turning into the gap to your left as you pass it. that when he does not go into the same gap, you get extra cautious not knowing that he is simply moving in to his girlfriend's house, and that the person moving in to his previous house is the one to be afraid of, and when you dobn't have that insight, many of us don't have dreams or goals to chase after, thus making us lost, confused and not knowing where to go.I hope this helped you! Comment if you want more information, or anything else!