Although the term "polyamory" wasn't invented until the 1980s, the idea is old: loving more than one person at the same time. While Cassie would never have thought of herself as on the cutting edge of social change, she is actually way ahead of her time. She's an early Feminist, and her sexual adventures are not only more radical than most of the women of the 1970s, but put her squarely in the tradition of ground-breaking trendsetters.
Today men and women have a variety of choices about their love lives and sexual identity. Whereas Cassie was mocked by lesbians at Yale for being a "fence sitter," and "refusing to choose," women today can love whomever they want, and don't even need a label. There is even a cachet now to being bisexual, something that definitely wasn't there when this novel takes place.
Taking a break from Chapter Five, I wanted to provide some links to sites about polyamory, including the beautiful cloisonne pin shown above, which can be purchased from the Poly and Proud website (along with t-shirts that harken back to the 70s with slogans like "question monogamy").
The most prominent poly sites are "Poly Matchmaker," "PolyLiving" and "Polyamory Weekly" (a podcast of polyamory topics and fun stuff). "Poly Matchmaker" has lots of information about "ethical non-monogamy," and is also something of a dating tool for those who want to meet others with the same ideas. From all I could gather, polyamory is not the place to meet casual sex partners: there's a strong disdain for casual sex in some of the things I've read.
Indeed, polyamorists (or "polys" as they prefer to be called) are often confused with swingers, yet their goals are more about relationships than casual sex. So their sites and writings tend to sound like those from the early GLBT movement, including "coming out" to friends and family, and legal protection, including a desire to have group marriages. Cassie would've thought she'd died and gone to heaven if she had been able to have P. and S. under one roof.