A rare moment of gender parity in philosophy: Simone de Beauvoir and Jean-Paul Sartre at a Paris cafe in May 1970. STF/AFP/Getty Images hide caption

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A bride and groom exchange rings during a traditional Indian wedding ceremony. Although most marriages in India are still arranged, a growing number of women are taking matters of the heart into their own hands, using social networking clubs and matrimonial websites. iStockphoto.com hide caption

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Sheryl Sandberg, Facebook's chief operating officer, speaks at a luncheon for the American Society of News Editors in San Diego. Gregory Bull/AP hide caption

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French Minister for Women's Rights and Government Spokesperson Najat Vallaud-Belkacem wearing pants. Lionel Bonaventure/AFP/Getty Images hide caption

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