Helen Fisher's courageous investigations of romantic love -- its evolution, its biochemical foundations and its vital importance to human society -- are informing and transforming the way we understand ourselves.

Fisher describes love as a universal human drive (stronger than the sex drive; stronger than thirst or hunger; stronger perhaps than the will to live), and her many areas of inquiry shed light on timeless human mysteries, like why we choose one partner over another.

Brene Brown is a research professor at the University of Houston Graduate College of Social Work.

Brown studies human connection -- our ability to empathize, belong, love. She has spent the past ten years studying vulnerability, courage, authenticity, and shame.

She is also the author of The Gifts of Imperfection: Let Go of Who You Think You're Supposed to Be and Embrace Who You Are.

Sherry Turkle is a Professor of the Social Studies of Science and Technology at the Massachusetts Institute of Technology.

Having obtained her undergraduate degree of BA of Social Studies and later her Ph.D. in Sociology and Personality Psychology at Harvard University, she now focuses her research on psychoanalysis and human-technology interaction.

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