在 Penn 2018 年关于城市环境共享认知的研究中，他提出建成环境是人类社群认知机制的一部分，并参与社会演化（Penn, 2018）。基于这一观点，他进一步指出：人类在体验物质世界时建构意义，而这些意义会在社群成员与建成环境共同生活的过程中，于所有成员的心智中得以重构（Penn, 2018）。换言之，建成环境通过强化个体对物质环境的认知，以”意义”为纽带增强社会凝聚力。

一方面，我们可以将 Penn 所提出的”意义”理解为建成环境的象征性特征。这类象征性特征通常在一个区域内具有高度影响力与代表性，并最终通过强化个体对场所的认知来巩固社群联结。从城市尺度看，典型案例如巴黎的埃菲尔铁塔、凯旋门及历史轴线，如图 1 所示。从微观尺度看，典型例子可能包括某居住区中唯一的茶馆、某社区内的老教堂等。这类城市环境认知可称为显著模式（salient mode）：由于特定的文化背景、创新的建筑形式、独特的功能等赋予其象征性，建成环境的意义总能被场所中的社群成员清晰表达、理解、讨论与传播。

另一方面，”意义”也可能指一种人们不易察觉的共存机制，即 Hillier 在《Space Is the Machine》中提到的虚拟社群（Hillier, 1996, p169）。基于 Hillier 的观点，建成环境的空间设计创造了一种基本模式，决定人们在特定场所有多大概率相遇，并最终影响社群中的共在（co-presence）与共知（co-awareness）（Hillier, 1996, p169）。例如，某居住区中某一空间的整合度（integration）很高，导致人们在此聚集、交谈甚至开展各类活动，社群成员逐渐对这一充满活力的社区空间形成认知，如图 2 所示。这类城市环境认知机制可称为隐模式（hidden mode），因为人们常常并不清楚为何人群会聚集于此，以及这种局面是如何形成的。

在显著模式下，规划师的设计往往预先嵌入整个城市环境的演化与发展过程。此时城市规划通常基于象征性意义，而缺乏可计算地证明何种配置更优。原有的象征性特征或被破坏或被保留，而结合传承与创新、在城市环境中涌现的新象征性特征则逐一被创造，从而完成城市环境的演化。

空间句法的发明为城市规划与设计提供了隐模式视角，使规划者开始理解空间配置的潜在影响，并将其纳入设计考量，如图 3 所示。从认知角度看，这一发明具有革命性意义。它深化了我们对人类社群认知机制的理解，并将在未来城市环境的演化中发挥重要作用。

参考文献

Penn, A., 2018. The city is the map: Exosomatic memory, shared cognition and a possible mechanism to account for social evolution. Built Environment, 44 (2). p.162-176.

Hillier, B., 1996. ‘Can architecture cause social malaise?’, in Space Is the Machine. Cambridge: Cambridge University Press. p.138-170.

In Penn’s study of shared cognition of urban environment in 2018, he proposed that the built environment is a part of the cognitive mechanism of the human community and contributes to social evolution (Penn, 2018). Based on his idea, he further mentioned that humans make meanings when experiencing the physical world and these meanings are reconstructed in the minds of all the community members when they live with the built environment (Penn, 2018). In other words, the built environment strengthens social solidarities through meanings, based on individuals’ cognition of the physical environment.

On the one hand, we may understand the “meaning” proposed by Penn as the symbolic characteristics of the built environment. Such symbolic characteristics are usually very influential and representative in a region, and ultimately strengthen the community connection by strengthening individuals’ cognition of the place. From the urban scale, typical cases are like the Eiffel Tower, Arc de Triomphe and the historical axis in Paris, as shown in Fig.1. From a micro perspective, typical examples may be the only teahouse in a residential area, an old church in a neighborhood, etc. Such a kind of urban environment recognition may be named the salient mode, as the meaning of the built environment can always be clearly expressed, understood, discussed and disseminated by community members in the place because of its symbolic given by its specific cultural background, innovative architectural form, unique function, etc.

From the other perspective, “meaning” may refer to a coexistence mechanism that people do not easily notice, which is the virtual community mentioned by Hillier in his book Space Is the Machine (Hillier, 1996, p169). Based on Hillier’s idea, the spatial design of the built environment creates a basic pattern that determines how likely people are to meet in a particular place and ultimately affects the co-presence and co-awareness in the community (Hillier, 1996, p169). For example, the integration of a particular space in a residential area is very high, which causes people to gather here, chat, and even hold various activities, and finally, members in the community gradually have cognition of such a lively community space, as shown in Fig.2. Such a cognitive mechanism of urban environment may be called the hidden mode, because people often do not know why people gather here and how such a situation is formed.

Under the salient mode, the design of planners is often preconceived in the evolution and development of the entire urban environment. Urban planning is often based on symbolic meaning in such a situation, and there is no calculation to prove which configuration is better. The original symbolic features would be destroyed or retained, while the new symbolic features in the urban environment, combining inheritance and innovation, would be created one by one, completing the evolution of the urban environment.

The invention of space syntax provides a hidden mode perspective for urban planning and design, allowing urban planners to begin to understand the potential impact of space configuration and incorporate it into design considerations, as shown in Fig.3. From a cognitive point of view, such an invention is revolutionary. It improves our understanding of cognitive mechanism of human communities and will play an important role in the evolution of the urban environment in the future.

Reference

Penn, A., 2018. The city is the map: Exosomatic memory, shared cognition and a possible mechanism to account for social evolution. Built Environment, 44 (2). p.162-176.

Hillier, B., 1996. ‘Can architecture cause social malaise?’, in Space Is the Machine. Cambridge: Cambridge University Press. p.138-170.