Colloquium Mathematical Philosophy, Paula Quinon (Lund) gives a talk at the MCMP Colloquium (27 November, 2014) titled "Natural numbers in philosophy of mathematics and in cognitive science". Abstract: Natural numbers are the object of studies in various disciplines. Two such disciplines are the philosophy of mathematics and research in developmental cognitive sciences. My current endeavor consists in studying the borders and possible mutual influences between these two. In my talk I compare the conceptual frameworks of the two disciplines to highlight similarities and differences. I provide examples of how the application the results from one discipline to the other may fail. I use these to consider how interdisiplinariy on the subject of natural numbers can be made fruitful. I will suggest that methodological contraints may be prudent to this.