方圆,拳谚有云:“横撑开放,光线茫茫,谓之方;提抱含蓄,中藏生气,谓之圆。”太极拳以十三势立名棚捋挤按为四正门,亦即四正手;采捌肘靠为四奇门,亦即四隅手,前进、后退、左顾、右盼、中定为五步,“定在方中”土也。“中土不离位”,拳脚展开,范围八卦而成“方”,严格地说是“横撑开放,光线茫茫”的不规则多边形。在拳法中则代表一种外散的力。然虽为“外散”,却又寓意有形和封闭。但控制多边形,包括方的最好形状是圆,此即紧凑为圆,因此从拳术的角度讲,内家太极拳的轮廓是圆(从立 Radius, boxing saying goes: “cross-open, the vast expanse of light, that the party; to hold the implicit, Tibet angry, that circle.” Four forehand; mining elbow by four odd doors, that is, four corners of the hand, forward, back, left care, right hope, in five steps, “set in the party” soil too. “China and Turkey are not out of position,” Fist kick out, the range of gossip and made “square”, strictly speaking, “cross open open, vast expanses of light” irregular polygons. In the boxing it represents a kind of power to disperse. Although it is “scattered”, it implies that it is tangible and closed. However, the best shape of the control polygon, including the square, is a circle, that is, the circle is compact. Therefore, from the point of view of martial arts, the outline of a Taiji box is a circle