Used Book Sales Surge Against the Tide in the AI Era — What's Behind It?

A Counterintuitive Phenomenon

In an era where digitalization has swept the globe and generative AI is nearly omnipresent, a seemingly contradictory phenomenon is unfolding: sales of secondhand physical books are booming. When ChatGPT can summarize a book's core arguments in seconds, and when e-books and audiobooks make reading more convenient than ever, why are more and more people turning to used books — the most "traditional" medium of all?

This trend has sparked widespread discussion. On the surface, the explosion of AI technology should further squeeze the survival space for physical books, yet real-world data points in the opposite direction. What this reflects may be a renewed craving for "authenticity" and "certainty" in the age of AI.

The Hidden Connection Between the AI Boom and the Used Book Surge

A Renewed Emphasis on "Trustworthy Content"

As generative AI achieves mass adoption, the internet has become flooded with AI-generated content — from blog posts to e-commerce reviews, from news summaries to "expert guides." Generative AI refers to artificial intelligence systems capable of creating entirely new content based on training data. Representative technologies include OpenAI's GPT series, Google's Gemini, and various open-source large language models. These systems, built on Transformer architectures and large-scale pretraining, can produce text, images, audio, and other content at extremely low marginal cost. By some estimates, the share of AI-generated or AI-assisted content on the internet has risen significantly by 2025, with some content farms churning out thousands of articles per day. While this leap in production efficiency has lowered the barrier to content creation, it has also triggered what information ecologists call the "content dilution effect" — when supply grows infinitely but quality filtering mechanisms fail to keep pace, high-quality information actually becomes harder to identify.

This content deluge has produced a notable side effect: the credibility of information is being diluted. At the core of this content credibility crisis is the dramatic rise in "source verification costs." In the pre-AI era, the cost of producing content itself served as a quality signal — writing a book required months or even years of investment, and this high cost naturally filtered out large volumes of low-quality information. AI has reduced the marginal cost of content production to near zero, rendering the traditional "cost as quality signal" mechanism ineffective. The economic theory of "lemon markets" applies here: when consumers cannot effectively distinguish between high-quality and low-quality content, the market value of premium content gets dragged down, potentially leading to a "bad money drives out good" scenario.

Physical books — especially classic used books that have stood the test of time — represent a source of knowledge with certainty. They've gone through layers of editorial review, proofreading, and publishing processes. Their authors are clearly identified, and their content won't change because of a model update. Publications — particularly time-tested used books — serve as natural barriers against information market failure due to their historically high production costs and unforgeable physical existence. In a world where it's increasingly difficult to tell "what was written by a human and what was written by a machine," a tangible old book provides a reassuring sense of certainty.

An Emotional Outlet Against Digital Fatigue

Another important driving factor is "digital fatigue." When people's work, social interactions, entertainment, and even reading are all dominated by algorithms and screens, leafing through a physical used book becomes a rare "offline" experience. The value of this experience is amplified precisely against the backdrop of AI's increasing penetration into daily life.

Digital Fatigue is a compound phenomenon involving cognitive psychology and neuroscience. Research shows that prolonged screen use leads to attention fragmentation, working memory overload, and blunting of the dopamine reward system. Surveys by the American Psychological Association show that over 60% of adults report feeling exhausted from constant digital connectivity. From a neuroscience perspective, paper reading and screen reading activate different brain regions — the linear reading of physical books is more conducive to deep comprehension and long-term memory formation, while screen reading tends to activate shallow processing pathways associated with rapid scanning. This explains why many people instinctively seek out physical books as a means of cognitive recovery after intensive digital work.

The physical attributes of used books — yellowed pages, annotations left by previous readers, the smell between pages — are things digital content cannot replicate. These "imperfections" actually constitute a unique appeal, allowing people to rediscover the ritual and warmth of reading.

The Compounding of Economic and Cultural Factors

The Practical Consideration of Value for Money

Beyond psychological reactions to AI, the thriving secondhand book market also has more straightforward economic drivers. Under inflationary pressure, used books offer equivalent knowledge value at prices far below new books. For budget-constrained students, researchers, and general readers, used books represent excellent value.

The maturation of online used book platforms has also significantly lowered transaction barriers. Global online used book trading platforms have undergone a remarkable evolution from niche to mainstream. Platforms like ThriftBooks, AbeBooks (owned by Amazon), and Better World Books have transformed what was once a fragmented secondhand book trade into an efficient digital marketplace through standardized grading systems (such as "Good," "Acceptable," and other condition ratings), global logistics integration, and algorithmic recommendations. In the Chinese market, platforms like Duozhuayu and Kongfuzi Used Books have similarly developed rapidly. These platforms typically adopt a C2B2C model, solving the pain points of information asymmetry and quality uncertainty in traditional used book transactions through centralized purchasing, quality control sorting, and resale, making cross-regional and even cross-border circulation of used books the norm. People can easily search, compare prices, and purchase out-of-print books from around the world — something almost unimaginable a decade ago.

Collection and Cultural Identity

Buying used books is also gradually becoming an expression of cultural attitude. In the fast-paced world of digital consumption, collecting physical books conveys an identification with deep reading and slow living. This shares the same cultural logic as the recent resurgence of vinyl records, film cameras, and other "retro" categories — finding anchors of certainty amid technological acceleration.

This phenomenon is known in sociology as "Technostalgia." German sociologist Hartmut Rosa's "Social Acceleration Theory" provides an explanatory framework: when technological change, social transformation, and the pace of life all accelerate simultaneously, people develop intense "desynchronization" anxiety and turn to objects with material certainty and temporal depth to reconstruct their sense of being. This isn't simply "turning back the clock" — it's a strategy for actively constructing stable identity in an accelerating society. Used books happen to simultaneously satisfy three psychological needs: materiality (touchable), historicity (bearing traces of time), and certainty (content cannot be tampered with).

Is AI a Cause or a Catalyst?

It's important to take a rational view: attributing the growth in used book sales entirely to AI may be an overinterpretation. The revival of the secondhand book market is the result of multiple factors working together: economic pressure, environmental awareness (reuse reduces waste), post-pandemic changes in reading habits, and the development of online platforms all play important roles.

AI's role is more likely that of a "catalyst" rather than the sole cause. It has intensified people's anxiety about content authenticity and amplified their fatigue with the digital world, thereby indirectly pushing some people back toward physical reading. In other words, AI is changing not only the technological landscape but also quietly reshaping consumer psychology and value judgments.

Implications for the Tech Industry

This phenomenon offers thought-provoking insights for the entire tech industry: technological progress does not always linearly replace old things. When a technology becomes too ubiquitous or even excessive, people often actively seek its "opposite" as a counterbalance.

For AI practitioners, this reminds us to consider a core question: in an era when AI can generate everything, what kind of content and experiences are truly scarce and valuable? The answer may be precisely those things with clear provenance, human warmth, and certainty. The counter-trend growth of used books is essentially the market's repricing of "trust" and "authenticity" as scarce goods.

In the future, as AI-generated content becomes even more pervasive, we may see more "human-verified" products and services emerge. This isn't resistance to technology — it's humanity's instinctive response to find self-balance in the flood of technology. This trend signals a new market stratification taking shape: at one end, AI-driven high-efficiency, low-cost content production; at the other, a "trust economy" whose core selling points are human creation, physical existence, and historical depth. The two are not opposed — rather, they form complementary poles within the information ecosystem.

Key Takeaways