If you see two numbers but they're both the same and you have to squint to read them, you have synesthesia, colorblindness, diplopia, and myopia.

"Combination Vision Test", by Randall Munroe, licensed under Creative Commons Attribution-NonCommercial 2.5 License

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If you see two numbers but they're both the same and you have to squint to read them, you have synesthesia, colorblindness, diplopia, and myopia.