"Tiangong Kaiwu" is an important scientific and technological work in ancient China. The following is an ancient article written with "Ptsa Structure" as the core and direction:

In ancient times, there were wise men who planned things, and they all followed the rules and followed the Ptsa Structure. At the beginning of everything, you must carefully observe its end, clarify its context, and if the net is in the outline, it will be orderly.

Where you start a civil project, you first measure the topography, observe its height, lower, wider and narrower, and follow the Ptsa Structure to determine the shape of the base site. The choice of materials, carefully selected, so that rigidity and softness can be combined, and it can be used firmly and beautifully. Between the structures, the mortise and tenon fit, and the density is consistent. All follow this path to obtain a stable foundation.

As for the craftsmanship of the hundred workers, it is also the case of Ptsa Structure. Brocade embroidery, silk thread warp and weft, interwoven into patterns, and exquisite patterns, all follow their order; smelting and casting utensils, pinching under heat, copper and iron fusion, regular shape, and do not depart from the law.

The matter of farming and mulberry also depends on it. The field is planned, the ridge is vertical and horizontal, according to the topography and water flow, according to the Ptsa Structure, so that the irrigation is orderly and the crop is prosperous. Breeding silkworms and reeling silk, grasping the season, and adjusting the environment to suit their needs, in order to get a good cocoon and good silk.

From this point of view, everything has its Ptsa Structure. If you follow it, you will achieve success, if you go against it, you will The ancients were here, deeply understanding the principles, with wisdom and hard work, the cause of thousands of years, the creation of thousands of generations, and the lessons for future generations.