【正文】 ng, process and purpose are expressed by its shapea bowl with an irregular edgeand the pattern of plantsbands of grasses and shrubs variably tolerant of fluctuating water levels。 it describes threedimensional space but neglects time. That does not mean that we should avoid using Euclidean geometry in the design of landscapes. Indeed, such use may heighten our perception of the natural forms of rivers and trees and the processes that produce them, especially when it is employed as a visual counterpoint that both expresses and contrasts with those forms. In Dinan, France, a monumental are of poplars takes its inspiration from the sweeping out the irregularities of the river bank. The are represents the idea of that sweep. Through the abstraction and echo of the horizontal form in the vertical dimension, in what is clearly a line inscribed by humans on the landscape, the experience of the river39。 they connect our bodies and minds to the pulse of the natural world outside our skin. The branching riverbed cut by flowing water and the branching tree within which the sap rises are patterns that mirror the branching arteries and veins through which our blood courses. Patterns formed by nature39。s order and human order prompts contemplation of what if means to be human. Design that resonates with a place39。s processes. The most intimate rhythms of the human body are still conditioned by the natural world outside ourselves: the daily path of the sun, alternating light with dark。 it embodies function,sensory perception, and symbolic meaning。 and it embraces both the making of things and places and the sensing, using, and contemplating of them. This aesthetic is concerned equally with everyday things and with art: with small things, such as fountains, gardens, and buildings, and with large systems, such as those that transport people or carry wastes. This aesthetic celebrates motion and change, enpasses dynamic processes rather than static objects and scenes, and embraces multiple rather than singular visions. This is not a timeless aesthetic, but one that recognizes both the flow of passing time and the singularity of the moment in time, and one that demands both continuity and revolution. Urban form evolves in time,in predictable and unpredictable ways, the result of plex, overlapping, and interweaving dialogues. These dialogues are all present and ongoing。 the monthly phases of the moon, tugging the tides。s natural and cultural rhythms, that echoes, amplifies, clarifies, or extends them, contributes to a sense of rootedness in space time. Process,Pattern,and Form Great,upright, red rocks,thrust from the earth,rising hundreds of feet, strike the boundary between mountain and plain along the Front Range of the Rockies. Red Rocks Amphitheater is set in these foothills, its flat stage dwarfed by the red slabs that frame it and the panoramic view out across the city of Denver, Colorado and the Great Plains. The straight lines of the terraced seats, cut from sandstone to fit the human body, and the tight curve of the road, cut to fit the turning car, seem fragile next to the rocks39。s processes and their symmetry across scales have long been appreciated by close observers of the natural world. Recent developments in science afford new insights into the geometry of form generated by dynamic processes, be they natural or cultural, and point to new directions for design. The forms of mountain ranges, riverbanks, sand dunes, trees, and snow crystals, are poised, jelled, at a moment in time, the physical embodiment of dynamic processes. Their beauty consists of a peculiar bination of order and disorder, harmoniously arranged, and the fact that their forms are at equilibrium, at any given moment, with the processes that produced them. Such forms and the phenomenon of their symmetry across scales of time and space, have recently been described by a new geometry,fractal geometry, which one of its originators, Benoit Mandelbrot calls the geometry of nature— pimply,pocky,tortuous, and intertwined. A sensibility steeped in classical geometry perceivers these forms as too plex to descibe. However, as fractals, such patterns can be described with simplicity, the result of repetitive processes, such as bifurcation and development. The variety of forms that stem from the same process os the result of response to differing conditions of context, of to the interaction with other processes. Strange and wonderful forms, mirroring those of nature, have been created by repeating a single puter program. Early in the process, the resulting form, as seen on the puter screen appears chaotic。s meander is intensified. Though set in a tight,evenlyspaced row along the banks of the river, the individual trees assert their own quirky growth, which is seen more clearly in contrast to the regularity of their placement. The interplay of different processes is also a subject of current research on chaos. Computer drawings illustrate the patterns that result when several rhythms, such as radio frequencies or plaary orbits, e together. Perhaps this is the contemporary version of the music of the spheres. They resemble a topographic contour map,prompting the realization that land form results from a similar interplay among multiple forces and processes, including gravity, water flow, and weather. Cultural processes also engage natural processes on the land。 even when riverflow was low, its form recalled that it was designed to receive. Olmsted39。 yet the sea is not full。 to downstream waterfalls is telescoped into a small space. The fountain permits and even invites human participation. The sheer volume and force of the waterfalls, the mystery injected by the many water sources, some halfhidden, the steep drop from streetlevel to the base of the fountain, and the dense screen of pines all cont