Puzzle: Zermelo-Fraenkel set theory is inconsistent
<|reference_start|>Puzzle: Zermelo-Fraenkel set theory is inconsistent: In this note, we present a puzzle. We prove that Zermelo-Fraenkel set theory is inconsistent by proving, using Zermelo-Fraenkel set theory, the false statement that any algorithm that determines whether any $n \times n$ matrix over $\mathbb F_2$, the finite field of order 2, is nonsingular must run in exponential time in the worst-case scenario. The object of the puzzle is to find the error in the proof.<|reference_end|>
@article{feinstein2003puzzle:,
    title={Puzzle: Zermelo-Fraenkel set theory is inconsistent},
    author={Craig Alan Feinstein},
    journal={arXiv preprint arXiv:cs/0310060},
    year={2003},
    archivePrefix={arXiv},
    eprint={cs/0310060},
    primaryClass={cs.CC}
}