Learning involves conceiving of common notions

We all share things which are “common” to all our bodies, such as the fact that we are made of flesh and blood, have brains and grow. These are:

If something is common to, and peculiar to, the human body and certain external bodies by which the human body is usually affected, and is equally in the part and in the whole of each of them, its idea will also be adequate to the mind. (Spinoza, 1994a, pp. 54, P 39)

In other words, we all have an adequate idea of walking because we all share a “common notion” of what walking is: that it is using two legs to move. (Jarrett, 2007, p. 67)

The foundations of reason are notions (by P38) which explain those things which are common to all, and which (by P37) do not explain the essence of any singular thing. On that account, they must be conceived without any relation to time, but under a certain species of eternity. (Spinoza, 1994a, pp. 60, P.44 Dem)