Beskrivelse

The famous duck-rabbit ambiguous image. Is it a duck? Is it a rabbit?

"The subject of a gestalt demonstration knows that his perception has shifted because he can make it shift back and forth repeatedly while he holds the same book or piece of paper in his hands. Aware that nothing in his environment has changed, he directs his attention increasingly not to the figure (duck or rabbit) but to the lines of the paper he is looking at. Ultimately he may even learn to see those lines without seeing either of the figures, and he may then say (what he could not legitimately have said earlier) that it is these lines that he really sees but that he sees them alternately as a duck and as a rabbit. ...As in all similar psychological experiments, the effectiveness of the demonstration depends upon its being analyzable in this way. Unless there were an external standard with respect to which a switch of vision could be demonstrated, no conclusion about alternate perceptual possibilities could be drawn." -- Thomas Kuhn, The Structure of Scientific Revolutions (3rd edn., p. 114).

Licensering

• Source: Jastrow, J. (1899). The mind's eye. Popular Science Monthly, 54, 299-312.

	Denne mediefil er offentlig ejendom i USA. Dette gælder for amerikanske værker, hvor ophavsretten er udløbet, ofte fordi dets første offentliggørelse fandt sted inden 1. januar 1929. Se denne side (på engelsk) for yderligere forklaring.
	Dette billede er formentlig ikke offentlig ejendom uden for USA; dette gælder i sær i lande og områder, der ikke anvender rule of the shorter term for amerikanske værker, såsom Canada, Folkerepublikken Kina (ikke Hong Kong eller Macao), Tyskland, Mexico, and Schweiz. Skaberen og udgivelsesåret er afgørende oplysninger og skal fremlægges. Se Wikipedia:Offentlig ejendom og Wikipedia:Ophavsret for flere detaljer.