Genius and madness

Genius and madness names one of the book’s central uncertainties: whether extraordinary intellectual power and psychological breakdown are opposites, neighboring states, or outcomes of the same relentless concentration. The idea is tested through cryptographers whose work demands unusual patience and ingenuity, but also isolates them from ordinary ways of thinking. In Rong Jinzhen’s story, the contrast becomes painfully concrete: he solves the PURPLE cipher, then is destroyed by a different encounter with the BLACK cipher. The novel does not make madness a simple synonym for genius; it shows how the label can obscure differences between achievement, illness, institutional failure, and the dangers built into secret work.

The Cryptographer and the Patient

The idea first takes institutional shape in the history of a celebrated cryptographer at Unit 701. Before Liberation, he had studied mathematics at Sun Yat-sen University, then been recruited by the KMT military and sent to Indo-China, where he cracked a high-level Japanese military cipher. After leaving the military in protest at Chiang Kai-shek’s decision to begin a second civil war, he worked under another name as a foreman for an electricity company in Shanghai. Unit 701 later tracked him down and recruited him back; he went on to crack several mid-level American ciphers and became its most successful cryptographer.

Two years before Rong Jinzhen meets him, schizophrenia abruptly changes how others see him. Once admired as a hero, he becomes someone colleagues fear because he may curse, shout, or strike out. His knowledge of important secrets prevents anyone from signing an order to send him to hospital, so he is treated at Unit 701’s clinic instead. The clinic’s doctors are surgeons, instructed in a few therapeutic methods by outside experts; their treatment calms him, but leaves him able to think of little besides chess. The account describes this as a transition from paranoid to catatonic schizophrenia, not as an achievement or a mysterious extension of his talent.

His chess fixation has a specific, consequential history. He learned elephant chess from a doctor while recovering. The experts later judged that the game had been introduced too early: concentrating a recovering patient’s intelligence on one object, they warned, could make it difficult to detach attention from that object. The doctor mistook the patient’s grasp of the pieces’ movements for evidence of recovery and continued playing with him. The result was a strong chess player whose attention had narrowed almost entirely to the board, rather than the full recovery that might have been possible. When he later finds Rong Jinzhen and repeatedly seeks him out for games, their meetings bring the institution’s lost cryptographic talent into the protagonist’s present.

The account locates responsibility not in an abstract kinship between brilliance and illness alone, but in circumstances that leave the patient confined in a mountain valley: his work had made him privy to too many secrets, and Unit 701’s medical response had failed. His chess could still reveal something of the intelligence he once displayed, while outside the game his capacities were described as drastically diminished. This contrast makes the label of madness both socially visible and intellectually inadequate: it marks a change in his condition, but cannot restore the person or explain away the decisions that helped shape his fate.

Two Paths Through Cryptography

The book extends the same problem from individual illness to the structure of cryptographic work. Its ordinary method is a gradual process of elimination: agents gather information, analysts form hypotheses, and they test possible keys against possible locks. The method is laborious and can seem crude, but its relative safety and effectiveness make it especially useful against high-level ciphers. Cryptography is also presented as unusually lonely labor. Its practitioners cannot easily build on a shared history or ask predecessors for directions; the field’s secrecy and obstacles leave each generation facing closed doors and side paths.

Rong Jinzhen’s alternative is to study the history of cryptography and use what earlier creators have done to narrow the search. This is the basis of his two-paths theory, an approach that risks entering territory other cryptographers have made dangerous. If it works, historical knowledge can eliminate some possibilities; the account offers the example of cutting away half of ten thousand byroads, while emphasizing that even such progress would leave an immense search. The method’s low prospects help explain why its practitioners might appear either fearless or reckless. The narrator says he could not tell whether Rong Jinzhen was a genius or a madman, and could imagine either astonishing success or tragedy. The distinction remains suspended until Rong Jinzhen decrypts the PURPLE cipher without telling anyone.

That success complicates the warning around PURPLE. Unit 701 had struggled with the cipher for years, and its people had become increasingly afraid to work on it. The story of the earlier cryptographer connects his breakdown with his work on PURPLE, making the cipher seem like a trap that can consume the person who attempts it. Jan Liseiwicz warns Rong Jinzhen not to touch it. Unit 701 interprets the warning both as evidence of the cipher’s difficulty and as a possible source of useful information, and sends a reply under Rong Jinzhen’s name. Yet the later account reveals that Jan Liseiwicz’s suggestions for breaking the cipher were wrong. Had Rong Jinzhen followed them, the narrator believes, they might have led him away from the solution. The episode makes good fortune, secrecy, and intellectual achievement difficult to separate: information withheld from Rong Jinzhen may have protected the very path that let him succeed.

A Theory of Shared Extremes

In a later conversation, the chess-playing cryptographer gives the concept a more general form. He argues that people with exceptional talent may pour their passion and intelligence into their work so completely that, in later life, they are left with memories of achievement rather than a need to seek a new outlet. People who have talent but cannot fully demonstrate it, by contrast, may continue searching for a way to use their abilities. He presents his own infatuation with chess as an expression of that unfulfilled search. This account makes chess more than a symptom: it is also an activity through which a person still tries to give his capacity direction.

He also describes genius as a narrow path. A person who has devoted years to intense study may become unable to turn freely toward other desires; the mind advances along the course it has learned to follow. In his formulation, genius and madness arise from a shared track but travel in different directions. He compares them to positive and negative infinities: opposed in sign, but alike in being without end. He even imagines that, with human development, someone regarded as mad might be recognized as a person capable of remarkable contributions. His speculation does not establish that madness contains hidden genius in every case. Instead, it questions the confidence with which observers divide capacities into useful brilliance and useless disorder, and insists that a person’s unrealized or inaccessible abilities cannot be measured by appearance alone.

The same connection is applied to cipher creation. Designing a cipher is described as work that draws its maker toward both genius and insanity; a cipher that no one could decipher would represent the extreme version of that creative possibility. The claim remains an analogy rather than a clinical explanation. Its force comes from the secrecy of the work: the creator may be separated from the people who would test the invention, while the codebreaker encounters an intelligence whose design must be inferred without ordinary communication or shared history.

PURPLE, BLACK, and the Cost of Insight

Rong Jinzhen’s later experience with the BLACK cipher gives the idea a harsher turn. After he has cracked PURPLE, the success creates a demanding comparison: he has proved himself against a formidable cipher and is ready for another opponent. Yet the BLACK cipher presents two apparently contradictory phenomena. The account attributes Rong Jinzhen’s failure to accept their coexistence to an assumption about how a high-level cipher ought to be made: because he knows the deliberation behind PURPLE, he cannot imagine that a sophisticated cipher would contain such an obvious contradiction. He becomes trapped by what the narrator calls artificial simplicity, unable to analyze the two elements together. His courage in confronting the problem is inseparable from the intellectual damage caused by that fixation.

The BLACK cipher is ultimately deciphered through a different route. Its key is zero, and the explanation is that it has no real lock: what appeared firmly secured was a false façade that could be opened simply by pushing. The narrator reaches this conclusion after seeing the leather attaché case as the place where the key was hidden, then tests the assumption at about three in the morning with the calculator capable of more than 40,000 calculations that had been given to Rong Jinzhen. He leaves the underground office in the mountain cave after solving the cipher, and the discovery is presented as an almost unbelievable reversal: an elaborate appearance of difficulty concealed an absence of a conventional lock.

The contrast is not that one man’s madness simply unlocks what another man’s genius cannot. Rong Jinzhen’s earlier success and later collapse both depend on how he directs his formidable concentration; the other cryptographer finds a solution by refusing the path that has trapped Rong Jinzhen. Unit 701 had also considered whether Jan Liseiwicz, who understood Rong Jinzhen, could have helped BLACK’s creators prepare against his skill. Their former closeness is set against political and ideological distance, and the organization learns that Jan Liseiwicz is Weinacht. In this context, knowledge can be protection, warning, or a means of anticipating an opponent; its value changes with who possesses it and what they do with it.

The account finally treats chance as part of the difference between a door that opens and one that does not. The narrator says that if the BLACK cipher had truly required a key, he would never have opened it; the false appearance of a lock made the solution possible. Even after the door swings open, he struggles to trust what he sees. The episode echoes the book’s wider uncertainty about talent and madness: achievement cannot be explained by intellectual power alone, and failure does not prove the absence of genius. Concentration may uncover a hidden path, or hold a mind fast to the wrong one; secrecy may protect a solution, or isolate the person most capable of finding it.