Poggendorff Illusion

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The illusion that the two ends of a straight Line Segment passing behind an obscuring Rectangle are offset when, in fact, they are aligned.

References

Burmester, E. ``Beiträge zu experimentellen Bestimmung geometrisch-optischer Täuschungen.'' Z. Psychologie 12, 355-394, 1896.

Day, R. H. and Dickenson, R. G. ``The Components of the Poggendorff Illusion.'' Brit. J. Psychology 67, 537-552, 1976.

Fineman, M. ``Poggendorff's Illusion.'' Ch. 19 in The Nature of Visual Illusion. New York: Dover, pp. 151-159, 1996.