Summary of the Core Content
This interview explores a fundamental question through architect Liu Yan’s 12-year research on the traditional technique of constructing wooden arch bridges: In the new era of AI technology, why do we need to reevaluate old techniques? Liu Yan uses the “seed, soil, growth environment” model to explain how these bridges, which are made by weaving wood into an arched structure, came into being and were passed down in the mountainous regions of Fujian and Zhejiang. She argues that old techniques are not merely outdated artifacts but represent a “pool of genes” that help us understand the patterns of technological evolution and address our anxieties about future advancements. These techniques can provide alternative solutions—like “backroads through the mountains”—that allow humanity to demonstrate its unique creative value in the future.
I. Wooden Arch Bridges: Techniques Forced by Environmental Constraints
What exactly are wooden arch bridges? Simply put, they are bridges built by interlocking and pressing wood pieces together to form an arched structure, without the use of nails, relying instead on mortise and tenon joints. These bridges did not arise out of leisure; rather, they were created due to environmental constraints:
- Bian Shui Hong Bridge: The Grand Canal during the Northern Song Dynasty was a vital economic artery, with many ships passing by. Since it was impossible to build piers (which could cause collisions), bridgeless “flying bridges” were needed, and wooden arch bridges proved to be ideal (the Hong Bridge depicted in the “Riverside Scene at Qingming Festival” is an example of this).
- Mountainous Regions of Fujian and Zhejiang: In these impoverished areas, building stone bridges was too costly. Stone bridges required extensive scaffolding (for instance, a wooden bridge had to be built first before constructing the stone one), but with wooden arch bridges, only long wooden beams were needed, simplifying the construction process and saving materials. The local people had no choice but to develop this technique to cross the rivers.
II. The Secret to the Survival of These Techniques: Seed, Soil, Growth Environment
Why have wooden arch bridges survived in the mountainous regions of Fujian and Zhejiang, while similar ideas (such as those found in Leonardo da Vinci’s manuscripts) did not? Liu Yan identifies three key factors:
- Seed: The initial technical concept (e.g., using wood to create arches).
- Soil: Social needs (e.g., the need to cross rivers in mountainous areas where piers could not be built on canals).
- Growth Environment: Conditions conducive to transmission (e.g., craft families in these regions, who practiced their skills diligently and passed down their knowledge to future generations. Additionally, the local skills in transporting wood and martial arts traditions helped preserve these techniques).
For example, although there are wooden bridges in the mountainous areas of Yunnan, the region’s abundance of resources meant that people did not feel the same pressure to develop such unique techniques.
III. From “Picking Peaches” to “Observing the Peach Tree”: A New Perspective on Studying Old Techniques
In the past, our study of traditional techniques was like “picking peaches”—we only focused on the useful parts (such as mortise and tenon joints in modern architecture) and discarded the rest (the process by which the techniques emerged and their relationship with the environment). Liu Yan’s approach is more akin to “observing the peach tree”:
- Not Rigidly Applying Scientific Methods: Traditional craftsmen did not use drawings; instead, they relied on oral traditions (e.g., “one foot high, three inches wide”). This does not represent mysticism but a different system of knowledge, similar to traditional Chinese medicine, with its own logic that cannot be dismissed by modern scientific standards.
- Focusing on the Whole Value: For instance, although wooden arch bridges have a maximum span of about 40 meters, their value lies in how they evolved in challenging environments and how they interacted with their surroundings. This understanding can help us appreciate the diversity of human civilization.
IV. The Value of Old Techniques in the AI Era: More Than Just Comfort
With the rise of AI, people fear being replaced by machines. What role can old techniques play? Liu Yan compares them to a “pool of genes” within biodiversity:
- Providing Diverse Perspectives: While AI follows a “high-speed highway” (aiming for speed and efficiency), old techniques offer alternative approaches (like the wooden arch bridge structure used by Pritzker Prize-winning architect Wang Shu in modern buildings).
- Demonstrating Human Uniqueness: Although AI can perform many tasks, the wisdom of traditional craftsmen (e.g., adjusting mortise and tenon joints based on experience) is something AI cannot learn. Old techniques can help us maintain our uniqueness as humans.
- Avoiding Monoculture: If all technologies follow the path of AI, it would be like an ecosystem with only one type of plant, which can lead to problems. Preserving old techniques provides a backup option for the future.
V. Deconstructing the Myths Around Old Techniques
Many people today exaggerate the merits of wooden arch bridges, presenting them as “miracles” that do not require nails or rivets. Liu Yan warns against this:
- Mythology Can Lead to Extreme Views: Either we overestimate the past (thinking our ancestors were perfect) or underestimate the value of traditional techniques. Both attitudes are unproductive.
- True Confidence Comes from a Balanced View: Wooden arch bridges have their advantages (e.g., material efficiency, suitability for impoverished areas), but they also have limitations (limited spans). True cultural confidence comes from understanding their place in history, not from exaggerating their significance.
For example, during the late Qing Dynasty and the Republic of China period, some people revived wooden arch bridge construction as a form of nostalgia, but this was not an opposition to new technologies like steel railway bridges; it was more about cultural identity. Today, we should not reject old techniques in favor of AI but allow them to coexist with modern innovations, just as people in the “Cloud Atlas” can choose between space exploration and traditional ways of life.
In Conclusion: Old techniques are not a thing of the past; they are part of the present. They help us understand our relationship with technology and our place within it. As Liu Yan says, “Only by understanding this moment can we know what comes next.” Old techniques are the keys to understanding the present.