People dream about things because those are the things they have missed when they were awake. People dream of beautiful women because when they are awake they have only their wife. It is the wife which is the cause of many saints: they renounce the world, because without renouncing the world they could not renounce the wife! The poor fellows had to renounce everything, just to escape from the wife.
Perhaps the proverb is true, that every great man has a wife behind him. Because she goes on nagging and harassing him and finding no other way he goes on succeeding, becoming richer, climbing ladders. The wife goes on hitting: “Go on!”… she never allows any rest for the poor fellow.
What can they dream about? They have never been hungry, they have never eaten anything; they cannot dream about ice cream. And certainly they cannot have nightmares which can awaken them.
Aesop has a beautiful parable. A cat is sitting on a tree, giggling and smiling. And a dog looks up and asks, “What is the matter, you idiot?”
And the cat says, “I was just having a beautiful afternoon nap and I dreamed that it is raining, very fast, strong rain, and the most amazing part is, it is not water that is raining, it is mice.”
The dog was very angry. He said, “You idiot. You will never grow out of your retardedness. In my holy scriptures there are instances when it has rained, but it has rained always cats, never rats!”
Obviously, a cat cannot think the way a dog can think, and they cannot agree. But if somebody is seeing rats and mice raining you can know that the person who is seeing the dream is a cat. There is not much logic involved in it.
Osho – The Great Pilgrimage: From Here to Here