The Necker Cube is an optical illusion first proposed by Swiss crystallographer Louis Albert Necker in 1832. The cube is a two dimensional line drawing that may be interpreted as a three dimensional cube in one of two orientations. The cube is often presented as a symbol of ambiguity and an illustration of the human brain’s ability to switch between two states of perception when presented with an ambiguous image.
The Necker Cube was first proposed as the symbol for androgyny in c.1996 by Raphael Carter in The Angel’s Dictionary, part of the Androgyny RAQ:
Necker Cube
n. 1. An optical illusion in the shape of a cube. May take either of two forms:
. . .
Proposed by the author as a symbol of androgyny, because it is either concave or convex depending on how you look at it. I prefer this to the mars-plus-venus sign, which depends upon a juxtaposition of stereotpyes (sword and shield for male, looking-glass for female), and which, furthermore, combines the signs for the two most irritating gods in the Roman pantheon. If we must depend on Greek mythology, I would prefer to take a cue from Janus and use some variation of the two-faces motif on the cover of some editions of The Left Hand of Darkness. The Necker cube, however, is simpler, and suggests ambiguity in more than mere gender. Who wants to design the lapel pin?
Practical Androgyny uses an adjusted form of the Necker Cube with a smaller square in the centre, as focusing on this square may allow the brain to break out of its cycle between two ‘equally possible interchangeable stable states’ and see the image for what it is; a two dimensional drawing which is neither of the interpreted cubes. Thus the androgyny symbol is itself an example of something that can be taken as one of two binary options or as something else entirely:
The Necker Cube is symbolic of the androgynous individual’s physical ambiguity. Regardless of whether we identify our genders in the terms of a gender continuum, as being without gender or as being something else entirely, the Necker Cube symbolises the ambiguity we present to a world that is primed to see all people as one of two binary options. Androgynous people can be taken as female, male or as something else entirely but, like the Necker Cube, our ambiguity invites those who interact with us to question what they see, and perhaps strive to see the true picture.
Practical Androgyny 
Heh, I have to agree with Raphael Carter, it’s an ideal image. It also makes for a good favicon!
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I just managed to see the Necker Cube as an Escher-type both at once (actually before it ‘flipped’ to the other common state), with (as in the Escher cube) some of the verticals in front and some behind in a way which can’t be done physically. And none of the shadings either helped or hindered seeing it in any of the three ways (in fact more than that, because I could also change which ones crossed). And as a flatspace hexagon which has been stretched on the diagonal. It’s a wonderful little picture, especially if you can see all of the possibilities at once, which makes it a good metaphor.
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I love escher, and his use of this symbol in particular. I never thought of this as a symbol of androgyny but I like the thinking behind that idea very much.
Thought to myself “I should get that as a tattoo.. oh wait I already have. I should appreciate that tattoo more.” 😉
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this is pretty rad. i think this cube is a brilliant symbol; i’m gonna doodle it on my pants.
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really love this, thank you.. a gorgeous idea.
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as an addition to my comment, I have always been a fan of this word
http://en.wikipedia.org/wiki/Quaquaversal
its vaguely appropriate! keep up the great work and thanks again : )
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[…] Some people immediately see one – or the other – and latch on to it. It’s very difficult for them to see the other side without goading, prompting and pointing. Others are puzzled by the illusion, and can’t bring any one side into clear focus. Usually once they make something out – however fuzzy it may be – that choice is now locked in. Though some prove to be more mentally flexible, and are willing to bend their brains to accommodate both realities simultaneously. The truly gifted can switch back and forth at will. Necker Cube – a symbol for Androgyny. […]
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