THOMAS A', the reputed author of the De Imitatione Christi, was born about the year 1380 at Kempen, near Cologne. His family name was Hämmerchen or Hämmerlein (in Latin, Malloclus), but he always called himself from his birth-place. Destined from an early age for the church, he was sent to receive the necessary training in a school at Deventer, belonging to the Brethren of the Common Life (gemeines Lebens). In his twenty-second year he joined the monks in the convent of St Agnes, near Zwoll, of which his brother, John a Kempis, was prior. After a noviciate of six years, he took the monastic vows, and remained a canon in the convent for the long period of sixty-five years. He died in 1471, at the advanced age of ninety-two. The greater part of his life seems to have been spent in transcribing books of devotion. One Bible in four folio volumes is mentioned which cost him fifteen years to copy and illuminate. His transcript of the famous essay on the Imitation of Christ has given rise to a controversy as to the authorship of that work, which has been keenly maintained, and is still as far from being decided as ever. Besides A' Kempis, two other candidates have been brought into the field, whose claims have been warmly advocated by their respective partizans. These are Jean Gerson, chancellor of the University of Paris, and Jean Gersen, whose supporters describe him as abbot of a monastery at Vercelli in the thirteenth century, while his opponents deny his existence altogether, and pronounce his name to be a corruption of Gerson's. The authorities for each opinion are pretty equally balanced. German and Flemish writers, countenanced by the Sorbonne, contend stoutly for A' Kempis; the French are equally zealous for their distinguished countryman; while the claims of Gersen are upheld by the most learned of the Benedictines. In favour of A' Kempis has been urged the testimony of many editions bearing his name, one of which is dated 1471, besides the wide-spread and generally accepted tradition which has ascribed the work to him ever since his own time. Against him, on the other hand, it is urged that he was merely a calligrapher or copyist; that the Chronicle of St Agnes, a contemporary work, makes no mention of his having written the Imitation, and that its name is not found in an early list of the works attributed to him. In support of Gersen are brought forward a great number of French and Italian editions, belonging to the fifteenth and sixteenth centuries, one of which bears date of Venice 1483. Gersen's claims are based on a very ancient MS., which ascribes the authorship to him directly, while he has the benefit of all the manuscripts held to be older than the times of Gerson and A' Kempis. The internal evidence furnished by the book itself is equally conflicting. On the one hand, the Gallicisms are very numerous, and such as could hardly have occurred to any one whose native tongue was not French. On the other hand, the whole spirit that breathes throughout the work is that of a solitary ascetic, who places the rule of life in absolute seclusion from the world, and seldom refers to the exercise of any social or domestic duty. As the first of these testimonies decidedly strengthens the case of Gerson, the second Kempten is equally conclusive against him; for the greater part of his life was spent in active duty as Chancellor of the University of Paris, and head of the Gallican church. Of late years, however, his claims have been very keenly pressed by the French critics, among whom Gence and Daumon are conspicuous; the former in various articles in the *Biographie Universelle*, and the latter in the *Journal des Savans* for 1826–1827. It may be doubted, however, if the controversy either will or can ever be settled. The work itself, which has been the subject of so much debate, has been often translated into the various European tongues, though it may be doubted if any of the versions can vie in expression with the concise and energetic, though somewhat barbarous Latin, original. It is calculated that it has now gone through 1800 editions, and that it has been more read than any other book except the Bible. With a deep knowledge of human nature and of the world, it breathes a spirit of the most refined and lofty devotion, while many isolated sentences are memorable for their beauty and heart-piercing truth. (See Hallam's *Liter. of Europe*; Bing, *Univers.*; Barbier's *Dissertation*; Napoleon's *Dissertation*; Ullmann's *Reformers*, &c.; Ersch u. Gruber's *Encyclopaedie*, &c.)