boundary of the republic of letters found that they did it at their peril.
Nevertheless, even with these limitations, the age succeeding that of Charles the Great, partly from the very imperfection of its intellectual vision, was able to venture upon enterprises which had perhaps been suppressed in their birth under more regular and better organised conditions. In the first century of Christianity it has been said that 'the disciples of the Messiah were indulged in a freer latitude both of faith and practice than has ever been allowed in succeeding ages.' A like criticism would be true with respect to the progress of thought after Charles's day. Not for many generations did philosophy assume that definite medieval guise in which it remained fixed until the dawn of modern history. The gates of theological orthodoxy were even less closely guarded. Hardly a century will elapse before we see, preparing or already matured, some of the characteristic problems of church-controversy, even then held of paramount importance, though none could foresee the sway they would hold over the minds of men hereafter. The sacerdotal basis of the church is attacked, the nature of the divine Trinity is subjected to cold analysis; the doctrine of predestination is revived, the doctrine of transubstantiation is formulated. Such were the unexpected fruit of Charles's and Alcuin's husbandry. In the two following chapters we shall examine a few specimens of the literature and the speculations of the ninth century. The first examples will be taken from a class of writings but indirectly connected with learned studies, and will illustrate the movement of thought with respect to religious, or, it may be, superstitious, usages and beliefs: the second chapter will attempt to delineate the character of the theology of the greatest philosopher whom Ireland sent forth to glorify the schools of continental Europe.
