Henry Davis 
Medieval Europe [EPUB ebook] 

All divisions of history into periods are artificial in proportion as they are precise. In history there is, strictly speaking, no end and no beginning. Each event is the product of an infinite series of causes, the starting-point of an infinite series of effects. Language and thought, government and manners, transform themselves by imperceptible degrees; with the result that every age is an age of transition, not fully intelligible unless regarded as the child of a past and the parent of a future…