%0 Journal Article %T Inconsistency of Measure-Theoretic Probability %A Guang-Liang Li %A Victor O. K. Li %J Mathematics %D 2014 %I arXiv %X We reveal a contradiction in measure-theoretic probability. The contradiction is an "equation" $1/2 = 0$ with its two sides representing probabilities. Unlike known paradoxes in mathematics, the revealed contradiction cannot be explained away and actually indicates that measure-theoretic probability is inconsistent. Appearing only in the theory, the contradiction does not exist in the physical world. So practical applications of measure-theoretic probability will not be affected by the inconsistency as long as "ideal events" in the theory (which will never occur physically) are not mistaken for real events in the physical world. Nevertheless, the inconsistency must be resolved. Constructive mathematics can avoid such inconsistency. There is no contradiction reported in constructive mathematics. %U http://arxiv.org/abs/1412.5411v1