Similarly, Laurel Richardson uses the metaphor of a crystal to deconstruct traditional validity (Richardson, 1997, p. 92). A crystal has an infinite number of shapes, dimensions and angles. It acts as a prism and changes shape, but still has structure. Another writer, Patti Lather, proposes counter-practices of authority that rupture validity as a "regime of truth" (Lather, 1993, p .674) and lead to a critical political agenda (Olesen, 2000, p. 231). She mentions the four subtypes: "ironic validity, concerning the problems of representation; paralogical validity, which honors differences and uncertainties; rhizomatic validity, which seeks out multiplicity; and voluptuous validity, which seeks out ethics through practices of engagement and self-reflexivity (Lather, 1993, pp. 685~686)" (Ellis, 2004, pp. 124~125).