(aviation) An illusory perception of one's pitch angle, due to the effects of linear acceleration on the vestibular system of the inner ear.

An optical illusion in which an arrangement of horizontal and vertical bars of various lengths may be viewed as either a series of rectangles or a series of circles.

(philosophy) An argument for the existence of sense-data, and thus a criticism of direct realism, according to which what we perceive (such as a stick that looks bent because it is viewed underwater) is distinct from the actual thing perceived (the straight stick).

plural of argument from illusion

(psychology) The psychological illusion by which people tend to believe that their personalities and preferences have reached a more or less stable state, despite recognising that these things have undergone significant change in the past.

An optical illusion consisting of a stylized arrow whose midpoint appears to be closer to the tail end.

Synonym of flash-lag effect

A tactile illusion where tapping separate regions of a person's skin in rapid succession (e.g. the elbow and the forearm) gives the impression of sequential taps "hopping" from one point to the next, even though the intermediate points were never touched.

An optical illusion where, when a diagonally striped pole is rotated around its vertical axis (horizontally), it appears as though the stripes are moving in the direction of its vertical axis (downwards in the case of the animation to the right) rather than around it.

An optical illusion in which the parallel straight dividing lines between staggered rows with alternating dark and light "bricks" appear to be sloped rather than parallel.