Writing was developed independently in China and the Middle East gradually between about 3,000 and 1,000 BCE.  Then it spread slowly to new culture centers and to various other languages.  Interestingly alphabetic writing (that is, writing using symbols for consonants and vowels) was invented only once, by the Phoenicians, a Semitic-speaking group in the area of Lebanon around 1000 BCE.  All other alphabets in Middle East, Europe and Southern Asia are directly derived from the Phoenician alphabet. In any case, in 283 BCE, the royal library of Alexandria Egypt was founded (shortly after the death of Alexander the Great), the first attempt at a ``universal library.''  It began collecting books in Greek, Egyptian, Hebrew, Aramaic, Persian, Latin and even some Buddhist literature from India, presumably in Sanskrit.  And by about the onset of the Common Era, the Chinese, Greeks and various Semitic groups in the Middle East were all writing significant amounts of material.

Definitions:
    1.  ideographic writing - uses symbols representing an idea, for example, using a picture of an ox head to mean an ox or cow.  These are found in early Egyptian hieroglyphics, Mayan hieroglyphics, etc. Typically the number of symbols is not very large and such systems are useful primarily as mnemonic devices for facilitate recalling texts that you memorized.
    2.  logographic writing - uses a symbol to represent each specific word, as in Chinese writing, both classical and modern.  Such a system must have many thousands of symbols since we all use many thousands of words.  But once one knows the system, the text can be read off word for word.  Notice that if pronunciations change over time, readability will hardly be reduced.   Modern Chinese can easily read texts that are 1000 years old. (But we have much trouble reading Shakespeare, only 400 years old.)
    3.  phonetic writing - each symbol represents a sound, not a word or meaning.  Both syllabaries and alphabets are types of phonetic writing. Such a system also permits exact reading of a text.  But, over long periods, as pronunciations change, such texts become less intelligible since people avoid changing spellings. (This is the case with English spelling which is only partially phonetic now.)
     4. consonant inventory - a set of symbols that represent only the consonant sounds of a language. The Classical Arabic and Hebrew writing systems are of this type.  Thus the word banana would be spelled as BNN.  In modern usage both  the Arabic and Hebrew systems represent vowels with small diacritic marks.
     5.  syllabary - a collection of symbols representing specific syllables.  Thus one symbol would represent `ba' and another `bi' and another `ma' and another `mi', etc.  Japanese uses such a system called `katakana'.  Such systems have been invented several times through history, including by a Cherokee Indian for writing Cherokee.  They are useful for languages with a very limited set of syllables.  Japanese, for example, has only a 100 or so syllables, but not for English with has thousands of them.  Cherokee writing uses 85 syllabic symbols.
     6.  alphabet - a set of symbols representing specific consonants and vowels.  The Greek alphabet (~1000 BCE) was the first alphabet. All modern alphabets are derived from this one: Greek, Latin, Russian, Indian, Tibetan, the International Phonetic Alphabet, etc.

  Middle East

4k-3k BCE  EGYPTIAN WRITING developed, hieroglyphics. Partly ideographic, partly a syllabary. Represented only the beginnings of words phonetically. Vowels and non-initial consonants were not represented and had to be guessed from the context.  Gradually the system became logographic and phonetic, so word-for-word reading became possible.

1700 BCE, Proto-Canaanite script.  Hebrews and related groups. Greatly simplified characters mostly derived from hieroglyphics. Only consonants. Used primarily for religious texts.

• 425-375 BCE  Plato (in Athens). He began composing texts in 399 BC apparently using a scribe to write his words down. His teacher, Socrates,  wrote nothing.
  
• 384-322 BCE  Aristotle's lifespan. A student of Plato after age 18 (in 366 BCE).  Aristotle read and collect books but apparently wrote no books or scrolls himself. His students wrote down his ideas in the books attributed to him. Aristotle was the tutor of Alexander.
  
• 340-323 BCE   Alexander's brief empire. Spread the Greek alphabet and language into Asia.
•   350 BCE-600 CE - FLOWERING OF GREEK CULTURE IN THE MIDDLE EAST, especially in
•   Alexandria, Egypt. Many papyrus texts were written and copied by hand at the library in Alexandria:
•   Homer, Plato, Aristotle, etc. Greek was dominant language of eastern Mediterranean until 100 BC, when Latin began to supplant it. Most of the contents of the library in Alexandria were burned or destroyed about 300 CE. 
  

            ____________  Start of Common Era ______



• [500-600 CE.  Complete collapse of the Roman Empire (with its culture and education system) by ransacking barbarian peoples (Celts, Germans, Huns).]
  

• [800 CE Europe in dark ages.  The literacy rate was again almost at zero! Knowledge of writing in Western Europe was preserved only in a few monestaries by the Church.]
  

• [900 CE  Charlemagne campaigns to restore strong literacy skills to the priesthood and religious officials.  Literacy for the aristocracy came later and came for commoners nearly a thousand years later.]

600 BCE   Brahmi script probably derived from Semitic. This became the basis for most scripts of southern Asia: Pali, Tibetan, Devanagari, etc.   

  [700 BCE  `Kharosti script' - based on Persian script.]

900 CE  DEVANAGARI script developed in northern India for Sanskrit. Derivatives of this script became the standard scripts of modern north Indian languages (eg, Hindi, Bengali, Gujarati, etc).   Why was a script for Sanskrit adopted so late?   Because Indians preferred to memorize the (Hindu) vedas and (Buddhist) sutras for transmission.

   CHINA

10k-4k BCE  Primitive ciphers on bones, turtle shells, sheep scapulas.  Presumably  ideographic although not deciphered.  Very few examples survive.

1200 BCE. `Oracle Bones' with complex characters. These suggest there may have been a full-fledged writing system at this time -- probably logographic, like classical Chinese writing (where each graphic symbol represents a specific word).

500 BCE   Writing done on bound papyrus strips, silk cloth and wood tables.  Many examples of Chinese writing are available by this time.

[221 CE   First Emperor of Ch'in standardizes Chinese writing which at this time varied greatly from region to region (that is, from dialect to dialect). This meant that speakers of dialects that were scarcely mutually intelligible could still read each others writings fairly well - an important unifying factor for the Chinese Empire.]

500 BCE-1200 CE  Mayan civilization (Yucatan, Guatemala)

250 BCE   Earliest Mayan script found, only partly deciphered. Probably ideographic.

[Aztec (200-1000 CE) and Inca (1100-1400 CE) writing were derived from Mayan script.  Not yet deciphered.]

1.  Thus, practical writing (and reading) methods were probably widespread among the noble class by about 800 BCE in China.  In the middle east, widespread practical literacy for some rabbis and the wealthy classes occurred by around 100 BCE.

2.  All sacred texts before this time were transmitted primarily orally.  So none of the great Indian religious texts (Vedas or sutras) were likely written down until AFTER 200 BCE, although the Vedas were composed around 1500-1000 BCE, the Baghavad Gita about 400 BCE, Panini's grammar of Sanskrit, 400 BCE and the early Buddhist sutras about 400 BCE.

3. In China, however, the ideas of Confucius and Lao-Tze were probably written down by others fairly shortly after their deaths.

4. It is often asked: WHY IS IT THAT SO MANY GREAT RELIGIOUS LEADERS APPEARED AROUND 500 BCE?

 The Great Early Sages of Mankind:
        Plato and Aristotle taught  ~400 BCE
        Tao Te Ching  (by Lao Tze) composed  ~700 BCE
        Kung Fu-Tze (Confucius)  lived ~600 BCE
        Zoroaster's texts (Persia/Iran): ~600 BCE
        Gautama Buddha - 550-480 BCE
        Isaiah -  lived ~700 BCE, book of Isaiah written ~500 BCE
        Jeremiah -  lived ~500 BCE

Port's answer: Because earlier great religious thinkers were forgotten before their words and message were written down.  The thinkers above are the first prophets and philosophers whose legends lived long enough to be written down!  We may call them the `early sages', but surely many great sages preceded them! But these are the first to have their ideas written down and their names and works remembered for all time.