With social networking sites enabling the romantically inclined to find out more about a potential lover before the first superficial chat than they previously would have in the first month of dating, this is an important question for the future of romance.

Lets assume that in looking for partners, people care somewhat about rank and and somewhat about match. That is, they want someone ‘good enough’ for them who also has interests and personality that they like.

First look at the rank component alone. Assume for a moment that people are happy to date anyone they believe is equal to or better than them in desirability. Then if everyone has a unique rank and perfect information, there will never be any dating at all. The less information they have the more errors in comparing, so the more chance that A will think B is above her while B thinks A is above him. Even if people are willing to date people somewhat less desirable than they, the same holds – by making more errors you trade wanting more desirable people for wanting less desirable people, who are more likely to want you back , even if they are making their own errors. So to the extent that people care about rank, more information means fewer hookups.

How about match then? Here it matters exactly what people want in a match. If they mostly care about their beloved having certain characteristics,  more information will let everyone hear about more people who meet their requirements. On the other hand if we mainly want to avoid people with certain characteristics, more information will strike more people off the list. We might also care about an overall average desirability of characteristics – then more information is as likely to help or harm assuming the average person is averagely desirable. Or perhaps we want some minimal level of commonality, in which case more information is always a good thing – it wouldn’t matter if you find out she is a cannibalistic alcoholic prostitute, as long as eventually you discover those board games you both like. There are more possibilities.

You may argue that you will get all the information you want in the end, the question is only speed – the hookups prevented by everyone knowing more initially are those that would have failed later anyway. However flaws that dissuade you from approaching one person with a barge pole are often ‘endearing’ when you discover them too late, and once they are in place loving delusions can hide or remove attention from more flaws, so the rate of information discovery matters. To the extent we care about rank then, more information should mean fewer relationships. To the extent we care about match, it’s unclear without knowing more about what we want.