The causes of language change are double-layered. On the top layer, there are social triggers. These set off or accelerate deeper causes, hidden tendencies which may be lying dormant within the language. The gun of change has been loaded and cocked at an earlier stage. In this chapter, we shall discuss this notion of underlying tendencies. Many of them appear disruptive. We shall therefore examine in particular changes which arise seemingly out of the blue to disrupt the language system.

Ease of effort, in the sense of ease of articulation, is the proposed cause of disruption which springs most easily to one's mind. There is a deep-rooted belief among quite a number of people that, were it not for the need to be understood, all human speech would be reduced to a prolonged uh. Ease-of-effort theories have been around for a long time. They were particularly prevalent in the nineteenth century, when educated men tended to idealize the ‘noble savage’, whose apparent virtues seemed to contrast strongly with the vices and decadence of civilization. At that time, we find the linguist Max Müller claiming that, owing to a laziness inherent in civilization, sophisticated people do not use the forceful articulatory movements required for primitive tongues.