Nothing.
Solve this Riddle!

footprints seems like a better answer
well you don't take footprints. Opposite problem.

I don't have eyes, but I once did see. I once had thoughts, but now I'm white and empty. What am I?
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The answer is "breath"
Well, if we look at science here, you technically breathe in oxygen, and breathe out carbon dioxide,right? And those two aren't the same thing.

I don't have eyes, but I once did see. I once had thoughts, but now I'm white and empty. What am I?
.
At first, I thought it was a mirror. Then I realized the answer was a skull. Is that right?

The answer is "breath"
Well, if we look at science here, you technically breathe in oxygen, and breathe out carbon dioxide,right? And those two aren't the same thing.
The more you "take a breath", the more you're going to leave behind your breath. Not about science but the expressions associated with the word. I didn't write the riddle.
What is greater than God, more evil than the Devil, invisible, and when you eat it you die?
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