THE SEARCH FOR PRINCIPLES UPON WHICH TO BUILD A THEORY OF ARCHITECTURE REVEALS THAT PLASTIC FORM IS THE FORM OF THE HIGHEST ORDER -- NOT BECAUSE IT IS BEAUTIFUL, ALTHOUGH IT POSSESS A BEAUTY THAT LASTS AS LONG AS THE FORCES THAT CREATED IT, BUT BECAUSE IT IS THE MOST EFFICIENT MEANS TO FUNCTIONAL REQUIREMENTS. THESE FORCES ARE CLASSIFIED AS: NATURE FORCES: Gravity Force--Wind Force--Water Force--Earth Force. SENSUAL FORCES: Sonic Force--Visual Force--Tactile Force. BEHAVIORAL FORCES: Personal Force--Circulation Force--Sociological Force. They are not listed as a hierarchy of forces, although Nature Forces should be considered as primary. Because these forces do exist in the shaping of form, their understanding is therefore a prerequisite for the designer. Before form may be created the forces that give form must be considered. Primitive man found Gravity Force to be the primary form giver to his dwellings. His materials were those of compressive strength (mud, ice) and their resultant forms were therefore compressive stress forms of similar shape. Later, when tensile strength materials were developed, forms of great beauty emerged as tension structures. Both compression and tensile strong materials were shaped by the Gravity Force to produce Plastic Form. Plastic Form is also produced by the Wind Force. As the wind shifts the desert's fora so it is the prime determinent in the shape of racing car and aircraft. The Water Force has shaped the surface ships of the past with great beauty and will become the prime force determining our sub-aquatic cities of the future. The Earth Force determines the shape of man's objects as they are placed upon and within the earth. Now consider Sensual Forces. Man's visual, sonic and tactile requirements also produce Plastic Form. As the Sonic Force has shaped our ear, so it shapes our theatre. Visual Force relates to man's sensitivity to light and how Plastic Form is shaped in consideration to light. The most intimate of all forces is the Tactile Force. This force gives Plastic Form to all objects man touches - from the coke bottle to the chair. Consider the Behavioral Forces or those forces resulting from man's co-existence with himself and other men. The Personal Force is the expressive force of man. When strengthened by experience and knowledge the designer may then create Plastic Form of his will. The movement of people produce the Circulation Force that shapes homes, theatres, cities. The Sociological Forces involved within the city are the most complex of all. With thorough understanding of these ten forces an environment of unity, beauty and efficiency may be created through Plastic Form.