From the ain’t cognitive sciences cool department.

I was checking out some grad student pages in cog
science (unlike philosophy, they seem to let students have web pages) and I
found this, on Yi D. Cheng’s
research page.

Did you know that
female faces are greener than male faces? Human observers use this information
to classify faces by sex when other more salient cues to sex (e.g., shape,
hair) are absent. Thus, we are wondering if human observers find that greener
female faces are more attractive. This work has been done in collaboration with
Katja Doerschner, Bruno Rossion, Michael J. Tarr & Dan Kersten.

My first thought was that this is a pretty neat
result, and of course I didn’t know it, and would never have suspected it. I
thought, why can’t departments that I’m in produce clever results like this,
instead of boring papers about how many people there
are in the world? Then I remembered, they do! (But I’m not sure that
attractiveness is that right thing to check for next. I’m reminded a little of
Robert Solow’s famous
quote about Milton Friedman. Scroll down a little on that link to find it.)

My second thought, thinking now as a philosopher of
content, was that I was being too hasty. I might not have explicitly
known that female faces are greener than male faces, but I did know it implicitly.
After all, I’m human (more or less) so I “use this information to classify
faces by sex when other more salient cues to sex are absent.” See, philosophy
can make contributions to serious cognitive science.

My third thought, thinking now as an
epistemologist, was that my second thought went too far. I might have
implicitly believed that female
faces are greener than male faces, and this belief might have been true and
suitably responsive to the facts, but that doesn’t make it knowledge.
After all, knowledge claims can be defeated many ways, and one of them is by
believing that the thing allegedly known is false.

My fourth thought, and my final one for now, is
that it wasn’t obvious before reading Yi’s page that I believed female faces
weren’t greener than male faces. I might have been negatively disposed towards
that proposition were I to have thought about it, but I’m not sure it went as
far as full-blown tacit disbelief. So maybe I did know it after all. There’s a
hard epistemological question here. How negatively disposed towards a
proposition must you be before your negative attitude is a knowledge defeater?