Most of Stanislas Dehaene's papers are excellent, if you're into that sort of thing: http://www.unicog.org/biblio/Author/DEHAENE-S.html http://www.unicog.org/b

Most of Stanislas Dehaene's papers are excellent, if you're into that sort of thing: http://www.unicog.org/biblio/Author/DEHAENE-S.html http://www.unicog.org/biblio/Author/DEHAENE-S.html #4, "The Number Sense", is particularly good.