Good SF -- good writing in any medium or genre -- draws on all of human history and culture. Reading the greats back in the '50s, I'd come across a reference to Plato, or Machiavelli, for instance, and wonder who they were, so I'd go look 'em up and that led to reading The Republic and the Prince so on. David and I grew up on writers who were rich in imagination and knowledge of humanity, so in the Starfist series we draw upon everything we know and all the experience we've had to create our characters and plots. You can't experience everything in life but the more omnivorous your reading, the greater your understanding and appreciation will be of events and people who've never touched you, and the deeper your understanding of life will become.<<<+)))