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An infinite -theorem, or an -theorem, involving two families and of sets, states that if in every infinite subset of , there are sets that are intersected by some set in , then there is a finite set such that for every , there is a with . We provide an example demonstrating that there is no -theorem for piercing compact convex sets in with lines by constructing a family of compact convex sets such that it does not have a finite line transversal, but for any , every infinite subset of contains sets that are pierced by a line.

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