"use colon instead?"

Fairbot does not play optimally on the PD\. $\\mathsf{Fairbot}$ does cooperate with another $\\mathsf {Fairbot}$, even if the code of the other agent is not exactly similar \(e\.g\. they can use different proof systems\)\. ? If $\\mathsf {Fairbot}$ is reasoning in a sound system such as first\-order arithmetic, then $\\mathsf {Fairbot}$ is also inexploitable; it never Cooperates when the opponent Defects\. However, $\\mathsf {Fairbot}$ cooperates with $\\mathsf {CooperateBot},$ the agent which simply always returns 'Cooperate'\. By the premises of the Prisoner's Dilemma, we ought to at least bother to Defect against a rock with the word "Cooperate" written on it\. $\\mathsf {Fairbot}$ fails to exploit $\\mathsf {CooperateBot},$ so $\\mathsf {Fairbot}$'s play is not optimal\.

use colon instead?