Formal script types developed in historical sequence, each yielding to the next chronologically.  Seal script, earliest and most diverse of formal scripts, was dubbed seal script in later times because it has survived largely as the script used in carving character seals.  As the principal script type for all writing, it prospered from the time of the earliest extant writing (about the seventeenth century BC) until the second century BC.  The diversity of seal script forms is the greatest for any script type for at least three reasons:  1) the great length of its period as the dominant formal script type, 2) the diversity both of the materials on which it was written and of the implements with which it was written, and, most importantly, 3) the political disunity of the later centuries of its period of dominance, which allowed the independent kingdoms of the Warring States period (403-221 BC) to develop styles of writing more individual than was usual in China.  This diversity was squelched by the Qin dynasty (221-206 BC), which gained hegemony over other independent states during the Warring States period.  Unifying China, the Qin established a single script as universal standard, a subtype of seal script later termed lesser seal script (xiao zhuan shu).  The pre-Qin varieties of seal script became classed as forms of greater seal script (da zhuan shu).  The greater and lesser seal scripts became the two major subtypes of seal script.

The Qin's unification of seal script styling was almost wasted effort, however.  Around 300 BC, even before the Qin house had unified the nation, clerks in back offices, trying to dispatch the growing paperwork required to manage and control an increasingly complex society, had begun to modify the rounded forms of seal script into a faster hand to achieve greater bureaucratic efficiency.

Left: a rubbing of the San (Shi) Pan 散盤 (ninth century B.C.). Right: running and cursive script in a letter by Mi Fu 米芾 (1072-1105).

So was born clerical script (li shu), the second type of formal script.  Seal script had been written, often at slow speeds, with inflexible tools that created strokes of even width.  But strokes of even width had become difficult to execute with the advent of the writing brush and its ductile tip.  Squared rather than rounded character forms and flexibility of stroke width are natural expressions of the ductile brush.  In a lingering influence of seal script, many of the strokes in clerical characters were of even width, but the press-down, lift-up motion natural to the brush caused several of the eight basic writing strokes (especially heng, na, and pie) to be written with flared endings.  This was the first fundamental change in graphic styling caused by the use of the flexible writing brush.  Other changes were from a (generally) tall character structure in seal script to a low oblong shape in clerical, and a change in the shape of stroke finials (both starting and ending) from rounded to squared.  Clerical served as the dominant formal script from about 200 BC to 200 AD.

Clerical script showed signs of yielding to the third formal script type, standard script (kai shu), about the second century.  In its early forms, standard script was called zhen shu or zheng shu, regular or model script, and had square characters with thick strokes similar to those of clerical script.  By the seventh century, a remarkable change.  The heavy, even strokes used in writing since seal script days had evolved under the influence of the ductile brushtip to strokes that varied constantly in width, expanding and narrowing with changes in brush pressure.  Stroke finials were more artfully formed into a variety of detailed shapes, and character structure, having evolved from the low, wide shape of clerical to the square outline of zhen shu, became tall and elongated in standard script (kai shu).

Informal scripts are derived from formal scripts.  Of the two formal script types, running script has the simpler history, quickly evolving as a fast version of standard script by at least the third century.  Running script abbreviates, links, combines, and eliminates some of the strokes of standard to arrive at a quickly- written yet easily recognizable version of its ancestor.

The history of cursive is more complicated.  Each formal script evolved a cursive form, but these greatly differ from one another, with the early forms of cursive closely resembling, and the later forms increasingly different from, their parent scripts.  Further, the distinction between running and cursive script types can grow ambiguous.  Both informal scripts abbreviate, link, combine, and eliminate strokes of their parent formal scripts, so the distinction between them is based less on general definitions than on the parent script from which they evolved:  only standard script, not seal or clerical, has a running script derivative.  To define cursive script negatively, it is any informal script that is not running script.

Cursive seal script (cao zhuan shu) has a characteristic additional to the omission or abbreviation of strokes typical of all subtypes of cursive.  Since seal script has strong tendencies toward formality and bilateral symmetry, departures from either indicate a cursive form.  For example, if, of two equal, parallel strokes on each side of a character, one is significantly shorter than the other, or if characters are severely skewed toward their upper left or right, or if characters are written with a clearly casual styling, these asymmetrical or casual traits indicate cursive forms of seal script even if the characters retain all the strokes required of a formal script.

Note that the abbreviated character forms of cursive seal script are sufficiently conservative that to non-readers they can be indistinguishable from the characters of formal seal script.  Only a reader will easily perceive whether there are small omissions or combinations of strokes that simplify the standard stroke arrangements of seal script into cursive seal.  There is also a second, independent meaning of "cursive seal," that invented by Zhao Huan-Guang (1559-1625).  He created his own cursive seal principally by adding ligatures between the strokes of seal script characters, something seldom if ever seen in archaic forms.  Zhao Huan-Guang's innovation is well known among calligraphers but has not been much followed.

Another subtype of cursive script is based on clerical script and termed draft cursive (zhang cao).  It is much closer than seal cursive to the forms of modern cursive.  It radically reduces clerical script's complex character structures to a few lines.  Its strokes are usually strongly curved rather than straight, often curving down the right side of the character to swing beneath it in a tight curl.  Compared to the greater economy of later forms, however, there are usually several strokes per character and often a number of dots, or dian, giving some passages of draft cursive a speckled appearance.  Draft cursive often retains one of clerical script's flared strokes, the so-called na stroke, which descends diagonally toward the lower right to end in a large triangular shape.  Finally, characters in draft cursive are independent of each other, without interconnections.  While draft cursive is based on clerical, their relationship is graphically distant, and the character forms of draft cursive constitute a new visual vocabulary requiring separate training to read.

to page 1. Shida outlined the history of tea drinking prefatory to discussing Yixing teapots.
to page 3. Matthew outlines the history of script types and talks about the art of Hu Lunguang (cont.)