1 The writing represents speech notion
Speech and writing originated independently of each other. Human speech probably appeared long time before writing. Earliest writings developed from drawings. They were of visual origin, as pictographs, ideograms. As time went by, writings were spatially arranged sequentially in lines, corresponding to the sequential property of speech in time domain. As writing systems evolved in the alphabetic direction, writings and speech associated with each other tighter and tighter, continuing to present day. The alphabets lost pictographic property. As alphabetic systems have replaced their pictographic  predecessors and gained prevalence, it seems natural to conclude that the evolution of writing systems is to better represent language sounds. This conclusion is elegant, intuitive, reasonable and basing on facts and researches. It certainly cannot explain some cases, for instance, the Chinese didn’t evolve into alphabet. However, the Chinese characters are blamed to be too complex to represent speech. The modern Chinese writing is more tightly associated with spoken Chinese than ancient Chinese writing does. Moreover, characters have been simplified in mainland China. Chinese writing looks like taking a small step towards representing speech. Little doubts have been casted on this conclusion, although many scholars consider writing as more than simply representing speech. Representing speech seems a destined direction. Let’s be a little skeptical on this natural conclusion.
Without rigorous proof, this conclusion is taken for granted by man due to its intuitiveness and accord to most facts and history of alphabets. Let me now ask some basic questions. Why alphabets better represent sounds than pictographs do? How to determine if a script is good at representing sounds? Are some alphabets better in representing sounds than other alphabets are? Should evolution be attributed to the spoken form, written form or the representing itself? These simple questions are not easy to answer. Why not attribute the evolution of writing to the visual form, then? That can certainly have more clarity and become simple as writing itself is visual creature. Why people still stick to the ‘represent speech’ notion then? Following are some possible reasons. Speech and writing both changed a lot over time. They associated with each other tighter and tighter and are considered same thing – language. Speech is considered primary in language, which is by far meant spoken language. Speech is associated with human nature, while writing is considered an artifact. There are two points. One is they associate with each other. The other is speech is primary. The latter is itself a profound, although taken for granted. Here we take neutral position and won’t try to approve nor reject it. As we have said, speech and writing has independent origins. The link between them is not preexisting. They are set up after longtime use. The resultant connection between writing and speech shouldn’t be taken as the cause for the writing to evolve. Rather, the characteristics of writing should be analyzed to explain how it evolves visually. Then, the speech-writing association’s influence on writing’s evolution should be addressed.
2 Visual evolution of writing
Evolution of writing is reflected in its visual characteristics. We can easily see the salient visual distinction between alphabets and pictographs. Alphabet is a standardized set of letters. They usually comprise tens of letters, and are derived from complex pictographic scripts. Pictographs are complex and huge in amount. It is understandable to think that they have not evolved visually. If evolved visually, why becoming simpler instead of more complex? If writing is taken as visual art, it should evolve towards greater complexity. However, writing is a means of communication, representing and recording knowledge. The clarity, convenience, efficiency and suitability for reading thus become main concern. At the beginning, drawings were to depict something directly, as pictures. They were arranged usually in lines to represent meaning continuously. Apparently, the complex pictographs are not easy to recognize, lowering reading accuracy. It affects the reading fluency since more time is spent fixating at one pictograph before moving to the next. Complex symbols are discarded or simplified to facilitate linear reading. Some symbols had simpler and clearer visual pattern and were more frequently used. Long time passed, only a set of symbols are left and standardized. We call them alphabets. The reduction in number, simplification and standardization facilitate visual manipulation and memorization, leading the alphabets to supersede pictographs. Alphabetic writing is more suitable for reading than pictographic systems. We use the word ‘legibility’ to denote the concept ‘fit for reading’, which we think is the central in evolution.
How legibility takes effect? What is the mechanism, then? In the present world, texts explode. Through internet, one can easily find texts of any subject. The scope of the written world is virtually indefinite. Nonetheless, text still comprises basic individual symbols. Analysis can be done on the symbols and sequence of symbols. By simply analyzing the symbols, we are not overwhelmed by the explosion. These symbols are read and written by human. They have effect on humans via the eyes and brain. Legibility principle originates during reading, and then operates in thinking and writing while visual info is stored and processed in the brain. Although legible symbols can be arranged well and read easier, the visual patterns themselves are not the reason for reading. People read because the reading material reflects real world which is of the reader’s interest. Reading material is existent beforehand. They have to learn and use existing system regardless of its legibility and tend to read the symbols they are familiar  with. However, Texts of different degrees of legibility have different effects. Legible writing is easily read, memorized, processed by brain and written out. Legible writing impresses the eyes deeper and operates in the brain more effectively and strongly. More writings of greater legibility are read and produced than those with less legibility. After processing by the brain, the text written out has the tendency of being better patterned than those that are read. That is to say, legible writings have greater power to stimulate one to write. As a result, the writings produced later tend to be more legible than the earlier, changing the appearance of the writing system. Legibility is individual-dependent. Individual’s writing changes are not at the same pace. Change of a writing system is a result of changes made by all individuals’ written works. The appearance of post-change system usually does not differ completely from pre-change system. This evolution is a long time process and might become noticeable after generations.
Legibility principle operates starting from individual symbols, then throughout entire writing system. The recognizability of symbol/word forms, inter-differentiability of symbols, and inter-differentiability of words are the basis of a script’s legibility. Symbols/words are elementary. The strength of a writing system is usually judged on its entirety  – its all written works, the area and people it covers, all knowledge it represents etc. The dominant system is not necessarily the most legible. But legibility will exhibit its power as more-legible writing system grows faster. Individual symbols/words are building units of whole system and, basically determine how the whole system looks like and the potential it can expand. Legible symbols/words can be organized better and expand further. Legible system possesses more written works or has the potential to be such. It can grow bigger and thus represent more knowledge, leading to its success. Symbols form words, sentences and eventually a whole system. Rules/grammar develops for word formation and arranging words together. There are also recommended ways of formatting and writing paragraphs, thesis and book, but they haven’t become rules. These rules and recommendations imply the characteristics of larger linguistic units, facilitating reading and expanding legibility from symbol level to phrase, sentence levels and throughout the entire system. As time goes on, more-legible system overpowers/replaces less-legible system.
3 Spoken language’s influence and practical factors
Without spoken language, writing would have definitely evolved differently as it has been.Writing itself is capable of evolving alone. But, in reality, speech influences its evolution significantly. Since they are associated, writing and speech influence each other . Writing and speech have their own characteristics, legibility for writing, pronounceability and comprehensibility for speech. During their interaction, they are affected by each other and in the mean time try to maintain their own characteristics. Almost all present-day writings are pronounceable. That seems evidence that writing represents speech. However, from another angle, we also see that almost all speeches are writable. It should be that they converge from independent origins into tight association, instead of simply one conforming to the other. Convergence is obvious in alphabetic systems but not in pictographic systems. Tighter association leads to greater inter-influence. Tightly-associated speech and writing achieve mutual benefits as writing stimulates more speaking and speech induces more writing. Via association, speech sounds came to be a major source of new word/expression creation. Some new symbols are created or borrowed to represent language sounds. Diacritics  are added to change sound value. These changes make writing representing speech better . As speech sounds can be represented by different written symbols/words/phases, the legibility (visual shapes) of symbols/words/phases is pondered over for choosing desired ones. During the interactions between speech and writing, sounds could affect the formation and evolution of writing systems. But the final determinant of its success is the visual legibility, fit for processing, easy to be memorized and systemized. The visual form, instead of association/interaction with spoken language, is the central and deterministic in writing systems evolution. Spoken language works as a bridge between meaning and writing. It is not central in evolution process. On the contrary, it attaches to its writing system for survival, growth and spread. We hypothesize that the writing systems evolve towards more-legible alphabetic systems by means of visual refinement, during interactions with speech sounds.
The evolution is complicated by dozens of practical factors. Firstly, the creation and spread of writing relies on tools, materials, media, such as pen, paper, printing and nowadays computer and internet. Technological advancement has transformed the appearance of writing as well as the way writing is created, exists and spreads. Secondly, being durable, existing written works inevitably resist the writing system reform or new scripts adoption, more written works, stronger resistance. Finally, writing system is used by people and associated with things in a society. Development of writing system therefore has to do with the people and things. Writing system is associated with country, religion, education, economy, law, science, culture and so on. It spreads and grows together with them. Writing system is often designated officially in a country or region. Its changes are thus of regulatory, political and even military concerns. These factors, speech and still other factors complicate writing’s history. Writing possibly doesn’t evolve along a straight line. Nevertheless, in their complex development history, writing systems with greater legibility will be adopted by more people and prevail. It is an extraordinary feat of writing to incorporate all these matters and present visually organized arrangement to humans.
4 The success of Latin alphabet and the future of written English
As the prevailing alphabet of present world, Latin alphabet and its systems exemplify the legibility and speech-writing association. It has been used for writing numerous spoken languages and prevails for many of them, regardless of what sounds the languages possess. Visual feature of its writing systems is responsible for its prevalence.
Not only alphabetic systems superseded pictographic systems, some alphabetic systems have replaced or are overpowering other alphabetic systems. Different alphabets have been hard-tied with their spoken languages. Perhaps all people will say their respective alphabets are best to represent their spoken languages. However, basing on legibility, their writing systems compete to grow for success over others. Latin systems gain momentum in all alphabetic systems, invading other systems. The superiority of Latin systems is in that they have simple and clearly inter-distinguishable letters, syllabic combination of letters and words possessing integrated visual characteristics. Every letter is well shaped with great recognizability. The letters are easily to be systematically arranged. The ascenders and descenders of lowercase alphabets make letter combinations and words more legible. In most cases, the uppercase letters are less legible and had been superseded by lowercase letters, although they represent same sound as lowercase letters do. On the top of Latin systems, English sits. The English’s fit for reading clearly demonstrates writing itself instead of representing speech is crucial for a system to gain advantage, as the English written works expand globally, beating other systems, in various speech communities. With greatest volumes of written works and great legibility, the English writing system has spread around the world, via ways including trade, academics, education, war, colonization and most noticeable nowadays – technological evolution.
Besides direct spread of Latin systems, the Latin alphabet is used to write languages originally written in other scripts (or none), a process called Romanization. Romanization can create new Latin alphabets-based system. For language already written in another script, most people consider Romanized system and original system as the same language, though. That is perhaps due to its direct representing original writing/speech. Although Romanized system is taken as original language, Romanization is in fact Latin alphabet’s expansion. The original language is annexed into Latin systems. Romanized system brings people closer to other Latin systems. Knowing the Romanized system, people are readily to learn other Latin systems. Romanization also brings new words into existing Latin systems, whose speakers use some Romanized words as foreign words, which would enter native vocabulary over time. Romanization continues due to the legibility of Romanized system. As existing Latin systems spread and grow, Romanization goes on to non-Latin system regions. Non-Latin systems are unlikely overpowered by Romanized systems alone, but it seems they would be overwhelmed by the overall expansion of Latin systems.
As representative of Latin systems, English writing system is growing through representing knowledge, recording speech sounds and borrowing, among other means. The trend of English’s dominance is continuing. Written English is used by more and more people in non-native regions and would eventually be adopted by all. English will also be spoken by more people following the spread of written English . Other writing systems may be replaced, Romanized or coexist with English.
Written English is systematic. It has 26 letters, established rules for word-formation and grammar. Will it evolve in fundamental level, i.e. its scripts, lexicon or grammar? Or it will only continue growth basing on current system and rules? In near future, radical change seems unlikely. English has become international language. Without challenge, its basic look would not change. Rather, it would grow upon existing system when other language, culture and new-found knowledge are represented. On the long run, radical change cannot be ruled out. Theoretically, its future can be studied from its visual feature and is governed by legibility principle. In reality, the evolution is now a global process with billions of people’s participation. That is absolutely very complex. It is shaped by writings of every individual.
 Non-sound ‘based’ systems, such as logographic system, often contain many symbols not picture-like. They can be treated like pictographic system in that they also don’t have well-established sign-sound correspondence. We discuss pictographic system. Conclusion can be easily generalized to other non-sound based systems.
 People usually feel the familiar system easier to read than unfamiliar ones. Thus, to analyze legibility, familiarity should be taken into account.
 Systems of the same script can be different. For instance, we consider English system as a different system from other Latin alphabet-based systems.
 Writing’s influence on speech is tremendous.
 It is the English alphabets without (or rarely use) diacritics prevails, owing to diacritics usually makes readability worse.
 The visual characteristics of alphabets make them fit for representing sounds and can account for the tightness of speech-writing association. Writing evolves visually towards the alphabetic forms which in the mean time associates more tightly with speech than pictographs did.
 This is and was probably the case for native English-speaking countries.