If you know the mass of Jupiter is NOT 1kg, that doesn't mean the exact mass is knowable. It is possible to have *some* knowledge, but still not have 100% certainty in the value.
It is simply not the case that knowledge is an all-or-nothing proposition. I can know that Jupiter is more massive than Saturn and not know the mass of either. I can know the value of the mass to 3 decimal places, but not to 9. That means the knowledge of the mass is not 100% certain.
But even more, we may be able to say that the data is *consistent* with a zero spatial curvature in the universe and that there are good theoretical reasons to think it is zero, but we still do not have 100% certainty the curvature is zero.
For that matter, unless you can be 100% sure you don't live in the Matrix, you cannot be 100% sure that chair you sit on is real.
Uncertainty is part of living in the real world. ALL measurements have error bars on them.
It is simply not the case that knowledge is an all-or-nothing proposition. I can know that Jupiter is more massive than Saturn and not know the mass of either. I can know the value of the mass to 3 decimal places, but not to 9. That means the knowledge of the mass is not 100% certain.
But even more, we may be able to say that the data is *consistent* with a zero spatial curvature in the universe and that there are good theoretical reasons to think it is zero, but we still do not have 100% certainty the curvature is zero.
For that matter, unless you can be 100% sure you don't live in the Matrix, you cannot be 100% sure that chair you sit on is real.
Uncertainty is part of living in the real world. ALL measurements have error bars on them.
