Ah so this captures his thinking about kinematic self reproduction, before Stan Ulam came up with the suggestion of abstracting it to what became cellular autom

Ah so this captures his thinking about kinematic self reproduction, before Stan Ulam came up with the suggestion of abstracting it to what became cellular automata. Then they were able to show a construction that was self replicating with great generality because it worked using a sort of Turing machine tape to guide its operations.