Quite apart from his merits as a theologian, his works on chronology, notably the /De doctrina temporum/ and the /Tabulae Chronologicae/would have been sufficient to place him in the first rank of the scholars of his period. In theology he is chiefly remarkable for the introduction and application of the historical method in his discussion of dogma, and hence he is referred to rightly as the "Father of the History of Dogma." His principal theological work is the /Dogmata Theologica/ (1644-50).
The splendid example of a scientific treatment of moral theology set by St. Thomas produced very little effect during the fourteenth and fifteenth centuries, for the simple reason that the /Sentences/, and not the /Summa/, was the text-book used generally in the schools.
Following along the lines marked out by Raymond of Penafort in his /Summa de poenitentia et matrimonio/ (1235) a large number of /Summae/or manuals for the use of confessors were published during the fourteenth and fifteenth centuries, the last of them being that of Silvester Prierias, one of the earliest opponents of Luther. One of the few writers of this period who undertook to give a scientific explanation of moral principles is St. Antoninus (1389-1459), the Dominican Archbishop of Florence, in his /Summa Theologica Moralis/.
The rejection of the /Sentences/ in favour of the /Summa/, and the reform decrees of the Council of Trent gave a new impetus to the study of moral theology during the sixteenth and seventeenth centuries. Most of the great writers of this period, Gregory of Valencia (1550-1603), Vasquez (1549-1604), Lessius (1554-1623), Banez (1528-1604), Medina (1527-81), Sanchez (1550-1610), Saurez, and De Logo devoted special attention to the underlying principles of moral theology, and in some cases to their practical application. The /De Poenitentia/ and the /Responsa Moralia/ of De Lugo served as models of what might be called mixed treatment, partly scientific and partly casuistical. The /Theologia Moralis/ of the Jesuit writer, Paul Laymann (1574-1635), the /Instructio Sacerdotum/ of Cardinal Toledo and the /Medulla Theologiae Moralis/ of Hermann Busenbaum (1600-68), which went through forty editions in his own lifetime, may be cited as examples of this method.
The controversy regarding Probabilism did not assume a serious aspect till the rise and condemnation of Jansenism. During this period the enemies of the Jesuits pointed to the approval given to Probabilism by the Fathers of the Society as a proof of the laxity of view introduced by Jesuit theologians. Whatever may be said of the system, one thing is certain, namely, that the Jesuit theologians were not the first to put it forward. It was followed in practice long before the institution of the Society of Jesus, was enunciated clearly enough as a theory by the Spanish Dominican Bartholomew Medina (1527-81) and was adopted, at least in their solutions of particular cases, by most of the great writers during the latter half of the sixteenth and the first half of the seventeenth centuries.
Amongst the most notable writers on ascetical theology of this period were St. Ignatius of Loyola, the author of the /Spiritual Exercises/, St. Teresa (1515-82) the zealous reformer of the Carmelites, St. John of God (1495-1550) the founder of the Brothers of St. John of God, the Dominican Louis of Granada (1504-88), St. Francis de Sales (1567-1622), the two Jesuit writers Alphonsus Rodriguez (1526-1616) and Louis de Ponte (1554-1624), and Jean Jacques Olier (1608-57) the founder of the Sulpicians.
