Meaning:

You use this proverb to say that if you have a difficult problem and cannot find the answer now, just go to bed and have a good night's sleep. You may find it tomorrow morning.

If someone says, "The best advice is found on the pillow," he/she means that it might not be good to worry about your problem now. You may be able to solve the problem after a good night's sleep. People often say "I'll sleep on it" to express the same idea.

Example:

Let's end this meeting now. I don't think we can come up with the answer tonight. We're all tired. Let's sleep on it. The best advice is found on the pillow.

Don't worry about it too much today. Go to bed now. The best advice is found on the pillow.

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