Natural objects are signs of other things and events. Clouds stand for rain; a footprint represents game or an enemy; a projecting rock serves to indicate minerals below the surface. The limitations of natural signs are, however, great. (_i_) The physical or direct sense excitation tends to distract attention from what is meant or indicated.[27] Almost every one will recall pointing out to a kitten or puppy some object of food, only to have the animal devote himself to the hand pointing, not to the thing pointed at. (_ii_) Where natural signs alone exist, we are mainly at the mercy of external happenings; we have to wait until the natural event presents itself in order to be warned or advised of the possibility of some other event. (_iii_) Natural signs, not being originally intended to be signs, are cumbrous, bulky, inconvenient, unmanageable. [27] Compare the quotation from Bain on p. 155. [Sidenote: Artificial signs overcome these restrictions.] It is therefore indispensable for any high development of thought that there should be also intentional signs. Speech supplies the requirement. Gestures, sounds, written or printed forms, are strictly physical existences, but their native value is intentionally subordinated to the value they acquire as representative of meanings. (_i_) The direct and sensible value of faint sounds and minute written or printed marks is very slight. Accordingly, attention is not distracted from their _representative_ function. (_ii_) Their production is under our direct control so that they may be produced when needed. When we can make the word _rain_, we do not have to wait for some physical forerunner of rain to call our thoughts in that direction. We cannot make the cloud; we can make the sound, and as a token of meaning the sound serves the purpose as well as the cloud. (_iii_) Arbitrary linguistic signs are convenient and easy to manage. They are compact, portable, and delicate. As long as we live we breathe; and modifications by the muscles of throat and mouth of the volume and quality of the air are simple, easy, and indefinitely controllable. Bodily postures and gestures of the hand and arm are also employed as signs, but they are coarse and unmanageable compared with modifications of breath to produce sounds. No wonder that oral speech has been selected as the main stuff of intentional intellectual signs. Sounds, while subtle, refined, and easily modifiable, are transitory. This defect is met by the system of written and printed words, appealing to the eye. _Litera scripta manet._ Bearing in mind the intimate connection of meanings and signs (or language), we may note in more detail what language does (1) for specific meanings, and (2) for the organization of meanings.