http://www.slate.com/Economics/Current/Economics.asp
Selections:
More Sex Is Safer Sex
The economic case for promiscuity.
_By Steven E. Landsburg_
You've read elsewhere about the sin of promiscuity. Let me tell you
about the sin of self-restraint.
...
_That's _why increased activity by sexual conservatives can slow down
the rate of infection and reduce the prevalence of AIDS. In fact,
according to Professor Michael Kremer of MIT's economics department,
the spread of AIDS in England could plausibly be retarded if everyone
with fewer than about 2.25 partners per year were to take additional
partners more frequently. That covers three-quarters of British
heterosexuals between the ages of 18 and 45. (Much of this column is
inspired by _Professor Kremer's research._)
So a socially valuable service is under-rewarded and therefore
under-supplied. This is a problem we've experienced before. We face it
whenever a producer fails to safeguard the environment.
All these problems--along with the case for subsidies--would vanish if
our sexual pasts could somehow be made visible, so that future
partners could reward past prudence and thereby provide appropriate
incentives. Perhaps technology can ultimately make that solution
feasible. (I envision the pornography of the future: "Her skirt slid
to the floor and his gaze came to rest on her thigh, where the
imbedded monitor read, 'This site has been accessed 314 times.' ") But
until then, the best we can do is to make condoms inexpensive--and get
rid of those subway ads.