the date of writing of the Acts of the Apostles, as also regarding _St. Paul’s_ attitude towards Judaism and Christian-Judaism, and departs from the modern Protestant view (cf. pp. 28-47, 79 _seq._, 86, 93 _seq._). “Protestant authorities on church-history,” he says elsewhere, “no longer take offence at the proposition that the main elements of Catholicism go back to the Apostolic era, and not only peripherically” (Theol. Literar. Zeitung, 1905, 52). In a speech, much commented on, which he made at his university January 12, 1907, Prof. _Harnack_, discussing the religious question in Germany, called attention to the fact that there has been quite a marked return to the Catholic standpoint: “From the study of Church history we find that we all have become different from what our fathers were, whether we may like it or not. Study has shown that we are separated from our fathers by a long course of development; that we do not understand their ideas and words at all, much less do we use them in the sense they used them.” He then draws out the comparison more particularly: “_Flacius_ and the older Protestants denied that _Peter_ had ever been in Rome at all. Now we know that his having been there is a fact well evidenced in history.” The motto of the older Protestants was that the Scriptures are the sole source of revelation. “But now, and for a long time past, Protestant savants have realized that the Scriptures could not be separated from tradition, and that the collecting of the New Testament Scriptures was a part of tradition.” “Protestants of the sixteenth century taught justification by faith alone, without works. In the absence of confessional controversy, no evangelical Christian would now find fault with the teaching which declares only such faith to be of any worth which shows itself by the love of God and of the neighbour” (Protestantismus u. Katholizismus in Deutschland, Preussisch. Jahrbücher 127. Bd., 1907, 301 _seq._). Many similar instances of science confessing Erravimus in regard to the Christian or Catholic position could be cited. They are an admonition to be modest, not to overrate the value of a scientific proposition, and not, with supreme confidence and infallibility, to brand it as an offence against the human intellect to let one’s self be guided by the principles of faith. Moreover, it has often happened that science emphatically and sneeringly rejected propositions, and called them false and absurd, which to-day are considered elementary.