What is it that no man ever yet did see, which never was, but always is to be?

Common Wrong Answers
“Yesterday”
Yesterday refers to a time that has already occurred, which people can remember or see in retrospect, contradicting the riddle's premise of something that has never been seen.
“Today”
Today is the present moment that everyone experiences and can see, making it inconsistent with the idea of something that has never been seen.
“Next week”
Next week refers to a specific time in the future that can be anticipated, but it is not as universally applicable as 'tomorrow' which is always the next day.
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