Notice! This article contains spoilers for Silo season 2 episode 6.
Silo season two makes Caesar's shifting cipher a crucial part of one of its major storylines, raising many questions surrounding what it means and how Lukas uses it. Although a lot has happened in Silo Season 2, some of the developments in her story are much more intriguing than others. For example, while Juliette's efforts to return home are compelling to watch, the political conflicts within Silo 18 are arguably more compelling than Juliette's journey.
Another interesting plot point that came up halfway through Silo Season 2's runtime revolves around Salvador Quinn, former head of IT at Silo 18. Bernard gains access to Salvador Quinn's last cryptic letter in Silo episode 5 of season 2, which, according to Meadows, reveals some hard truths about the world they live in. Although Bernard was unable to crack the code, Lukas implements some intriguing techniques, including changing Caesar, to decipher Quinn's letter.
The Caesar Shift Method for Decoding Ciphers Explained
Caesar's shift is among the simplest methods used to decode ciphers
Caesar's method of switching was named after Julius Caesar because he is said to have adopted the technique to send private messages to his allies. In cryptography, the Caesar cipher is known to be a type of substitution cipher in which the letters of a plaintext message are shifted to a fixed number of positions in the alphabet. For example, for a shift of 3 to the right, G would become J, while J would be M. Similarly, if a shift of 3 was applied to the left, J would be G and M would be J.
…Given that the people living in Silo 18 are significantly backward and also do not have access to advanced computers, it makes sense that the Apple TV+ sci-fi show would introduce the decoding method as a narrative device.
Because the core idea behind Caesar's move is quite simple, it's easy to implement. At the same time, as any message encrypted with the method can be easily decoded, it is not widely used for advanced cryptology operations due to its vulnerability. However, given that the people living in Silo 18 are significantly backward and also do not have access to advanced computers, it makes sense that the Apple TV+ sci-fi show would introduce the decoding method as a narrative device.
Why Lukas Kyle tests Caesar's move to decode Salvador Quinn's letter in Silo
Lukas uses the best of his reasoning skills without knowing much about the method
In Silo In the first few episodes of season 2, Meadows realizes that Lukas is incredibly intelligent when he tells her about his theories surrounding the glowing balls in the sky of the outside world. Impressed by his deductions about how stars work despite his lack of formal knowledge of astronomy, Meadows recommends him to Bernard. Because of this, Bernard later invites him to repair the hard drive he acquired from Juliette and asks him to decode Salvador Quinn's cryptic letter.
Although Lukas has no formal training in cryptology, he uses the best of his thinking skills to create a basic method for decoding the message. When Bernard learns about his method, he realizes that he used Caesar's change. Although the technique doesn't help them decipher Salvador Quinn's message in Silo In episode 6 of season 2, Lukas' impressive deduction and coding skills convince Bernard to make him his shadow and give him access to the Legacy.