I meant hypothetically speaking it could be wrong.
But I am 100% certain, not that these kinds of exact percentages matter.
Once again, precisely. If you could be wrong, and you acknowledge you could be wrong, then you *cannot* be absolutely certain. There is always that possibility of being wrong.
if it is 'highly unlikely' that you are wrong, then it is still *possible* you are wrong, which means you are NOT 100% certain. You would be very slightly less than 100% certain.