Full Idea
For present in us by nature are certain initial truths everyone knows, in which lie potentially known conclusions our reasons can draw out and make actually known.
Gist of Idea
Initial universal truths are present within us as potential, to be drawn out by reason
Source
Thomas Aquinas (Quodlibeta [1267], 8.2.2)
Book Reference
McDermott,Timothy: 'Aquinas: how to read' [Granta 2007], p.19
A Reaction
Note that these are truths rather than concepts, but that they have to be 'drawn out' by reason. This is Descartes' view of the matter, where the 'natural light' of reason is needed to articulate what is innate, such as geometry.