Blair studied at Harvard University, the University of Cambridge and Princeton University. At Princeton, she was the second graduate student of Anthony Grafton. She defended a dissertation entitled 'Restaging Jean Bodin: the Universae Naturae Theatrum (1596) in its cultural context' in 1990, which became the basis of her 1997 book.
Since 1996, she has taught at Harvard University. She was named a Harvard College Professor in 2009 for outstanding undergraduate teaching, and has received numerous teaching awards since then, including the Harvard Phi Beta Kappa Teaching Prize for 2018.[4] She received the Everett Mendelsohn Excellence in Mentoring Award in 2014. Four seniors for whom Blair was adviser won the Hoopes Prize for outstanding senior thesis, a prize that Blair herself won when a student at Harvard College.[5][6] She is on the Editorial Board of the Journal of the History of Ideas.
"Reading Strategies for Coping with Information Overload, ca. 1550-1700," Journal of the History of Ideas 64 (2003), pp. 11–28.
"Note-Taking as an Art of Transmission," Critical Inquiry 31 (2004), pp. 85–107.
"Natural Philosophy" in The Cambridge History of Science, vol. 3: Early Modern Science, ed. Katharine Park and Lorraine Daston (Cambridge: Cambridge University Press, 2006), pp. 365–405.
"Organizations of Knowledge," in Cambridge Companion to Renaissance Philosophy, ed. James Hankins (Cambridge: Cambridge University Press, 2007), pp. 287–303.
"Science and Religion," in Cambridge History of Christianity, vol. 6: Reform and Expansion, 1500–1660, ed. Ronnie Po-Chia Hsia (Cambridge: Cambridge University Press, 2007), pp. 427–45.
(ed. with Jennifer Milligan), a special issue of Archival Science 7:4 (2007) entitled "Toward a cultural history of archives," with a co-authored introduction, pp. 289–96
"Textbooks and Methods of Note-Taking in Early Modern Europe," in Scholarly Knowledge: Textbooks in Early Modern Europe, ed. Emidio Campi, Simone de Angelis, Anja-Silvia Goeing and Anthony Grafton (Geneva: Droz, 2008), pp. 39–73.
"Corrections manuscrites et listes d'errata à la Renaissance," in Esculape et Dionysos. Mélanges en l'honneur de Jean Céard, ed. Jean Dupèbe, Franco Giacone, Emmanuel Naya and Anne-Pascale Pouey-Mounou (Geneva: Droz, 2008), pp. 269–86.
"Disciplinary Distinctions before the 'Two Cultures,'" The European Legacy 13:5 (2008), pp. 577–88, in a special issue on "The Languages of the Sciences and the Languages of the Humanities," ed. Oren Harman.