In Pride and Prejudice, the gentle reader is reminded, “A lady's imagination is very rapid; it jumps from admiration to love, from love to matrimony in a moment.”

Jane Austen made that observation during an era that kept romantic young ladies under the close supervision of their parents. Only the most foolish, such as Lydia Bennet -- the Pride and Prejudice character who runs off with a knave, George Wickham -- would move in with a man before marriage and still expect a happy ending.

Today, however, young women are likely to be sexually involved with the man of their dreams well before they even meet his parents. So it should come as no surprise that wishful thinking propels many young women into “live-in” relationships, while their male partners bide their time before a job transfer or graduate school.

Now, in the wake of a study by Rand sociologists Michael Pollard and Kathleen Mullan Harris that found—surprise!—a  male-female divide on commitment and cohabitation--University of Virginia marriage expert, Bradford Wilcox offers some cautionary advice in the Atlantic that might prevent future heartbreak. 

Wilcox kicks off his discussion with a bracing truth:  “cohabiting young adults have significantly lower levels of commitment than their married peers. This aversion to commitment is particularly prevalent among young men who live with their partners."

Further, men are much less likely than women to view cohabitation as a mode of courtship.

Pollard and Harris found that the majority of cohabiting young men do not endorse the maximum indicator of relationship permanence: 52 percent of cohabiting men between ages 18 and 26 are not "almost certain" that their relationship is permanent. Moreover, a large minority (41 percent) of men report that they are not "completely committed" to their live-in girlfriends.

By contrast, only 39 percent of cohabiting women in the same age group are not "almost certain" their relationship will go the distance, and only 26 percent say they are not "completely committed". Not surprisingly, the figures above and below also indicate that married women and men are much less likely to exhibit the low levels of commitment characteristic of many cohabiting relationships today.

Wilcox prescribes a healthy dose of transperancy regarding motive well before the move-in date. Why? Because "cohabitation now serves" a variety of purposes:

people see it variously as a courtship phase, an economical way to save on rent, a venue for convenient sex, a prelude to getting serious, or an alternative to marriage.

[Y]oung adults often end up living with someone who doesn't share their relational goals. Couples considering living together would be wise to talk through the goals they want to accomplish in that move, and make sure they are on the same page.

In other words, 'playing house' distracts unmarried couples from grappling with issues that become important after  marriage, like is this a worthy mate, or will we be able to raise children together? In Pride and Prejudice, Elizabeth Bennet and Mr. Darcy engage in such deliberations and then take the plunge. Lydia and George Wickham's forced marriage is a patched up job.

That said, Wilcox's Atlantic post does not address the altered social context of American courtship: as the number of marriageable men continues to decline, women often  conclude they have no choice but to enter into ambiguous partnerships with no clear future path. As University of Texas researcher Mark Regnerus observed in a recent  Register interview, the law of supply and demand has given men in early 21st century America the upper hand. 

In Jane Austen's time, things were different. What changed, and what stayed the same?