"The philosophical unity so visible in Europe at the time of the Reformation and still perceptible during the seventeenth and eighteenth centuries began to disintegrate in the early years of the nineteenth century. The accession of new languages to the status of scientific languages, the rise of nationalistically minded generations of philosophers, the progressive multiplication of the professors of philosophy, many of whom became philosophical writers, created a new historical situation. Descartes wrote his 'Meditations' in Latin, so they were read at once in the whole of civilized Europe; one hundred year later, Condillac could not read Locke in the original, and when Kant published his masterwork in German, it remained for many years a sort of mystery philosophy chiefly known from summaries, interpretations, and even criticisms. It is therefore almost unavoidable to take into account the nationalities of the philsophers in the nineteenth century and, up to a point at least, to order their doctrines accordingly."
—from the Preface

Author - Etienne Gilson
Author - Thomas Langan
Author - Armand A. Maurer CSB