There is no reason or rule that states only the one making the positive claim had the burden of proof. It is on anyone making a claim. If if you claim something as false, you are still making a claim of truth
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It is said that an argument is what convinces reasonable men and a proof is what it takes to convince even an unreasonable man. - Alexander Vilenkin
If I am shown my error, I will be the first to throw my books into the fire. - Martin Luther
If I am shown my error, I will be the first to throw my books into the fire. - Martin Luther