Introduction to phonology
Human messages are sent by sound, gesture, written marks, body movement, and electronic impulses, but the usual channels are speech and writing. Some people confuse the two by taking speech to be an imperfect reflection of the "real" language, the written one. But although writing is important, phonology is a distinct system, and the more fundamental one through which we acquire the rest of language as children. Writing is learned later, if at all—billions of people around the world use their languages without the benefit of written marks. Moreover, writing is only a partial rendition of language, ignoring aspects such as intonation (the inflection of the voice) and stress (as in the difference between the noun object and the verb object). We should also note that the rules of language are generally based on pronunciation rather than orthography. For example, Spanish y 'and' is said to change to e before the vowel i. What is actually meant is the sound "i", not the letter i, since the change also occurs before hi: hijos e hijas. But it would still be wrong to state the change as occurring before the spellings i and hi, for it does not apply in agua y hielo (where hi represents a sound that is not the vowel "i" at all).
As Moulton (1970, 117) explained to teachers and students of foreign languages:
No ordinary writing system was ever designed to meet the needs of people who are
learning the language; it was designed only for those who already know the lan-
guage. No one can hope to achieve much success by looking at black marks on
paper (the writing) and then trying to make appropriate noises (the language).
Instead, he must first learn some of the language and then note how what he has
learned happens to be symbolized in writing. Writing is not a set of directions
telling us how a language should be pronounced; it is a method of reminding us on
paper of things that we already know how to say.
For this reason, linguists focus primarily on phonology rather than orthography as the basic signaling system of language.