Definition of "docible"

I doubt not but ye ſhall have more adoe to drive out dulleſt and lazieſt youth [...] then we have now to hale and drag our choiſeſt and hopefulleſt wits to that aſinine feaſt of ſowthiſtles and brambles which is commonly ſet before them, as all the food and entertainment of their tendereſt and moſt docible age.

, [John Milton], Of Education. To Master Samuel Hartlib, [London: […] Thomas Underhill and/or Thomas Johnson], page 3