Marcus Giaquinto's current research is about the epistemology of visual thinking in mathematics.
‘Russell on Knowledge of Universals by Acquaintance’, Philosophy, 87 (2012)
‘Crossing Curves: A Limit to the Use of Diagrams in Proofs’, Philosophia Mathematica, (III) 19 (2011)
‘The Linguistic View of A Priori Knowledge’, Philosophy, 83 (2008)
Visual Thinking in Mathematics: an epistemological study, Oxford University Press, (2007)
The Search for Certainty: a philosophical account of the foundations of mathematics, Oxford University Press, (2002)