Poggendorff Illusion

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Poggendorff's illussion

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Poggendorff illusion

Parallel lines appear to break the transversals off. The closer the inclination of the lines in the two families, the more pronounced is the effect.

This is a variant of another Poggendorff's illusion.

References

The Mind's Eye, Readings from SCIENTIFIC AMERICAN, W. H. Freeman and Company, 1986

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