In addition to ambiguous sentences, Wittgenstein discussed figures which can be seen and understood in two different ways. Often one can see something in a straightforward way — seeing that it is a rabbit, perhaps. But, at other times, one notices a particular aspect — seeing it as something. An example Wittgenstein uses is the “duckrabbit”, a picture that can be seen as either a duck or a rabbit. When one looks at the duck-rabbit and sees a rabbit, one is not interpreting the picture as a rabbit, but rather reporting what one sees. One just sees the picture as a rabbit. But what occurs when one sees it first as a duck, then as a rabbit? As the gnomic remarks in the Investigations indicate, Wittgenstein isn’t sure. However, he is sure that it could not be the case that the external world stays the same while an ‘internal’ cognitive change takes place.

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