In previous episodes, Twiki has regarded Crichton as his "son". In this episode, he reveals that this is because Dr. Goodfellow allowed Twiki to assist him in building Crichton.
Crichton did not recite the Zeroth law of Robotics, to which the other laws were subordinate, since it did not exist when the series was made. Asimov created the Zeroth law in his novel "Robots and Empire" (1985), as he felt that his initial three laws were insufficient to protect society at large. This law, which is basically a wider reaching variant of the first law, stated that a robot may not injure humanity or, through inaction, allow humanity to come to harm.
Twiki's official designation is T.W.K.E-4. He states this when his brain is temporarily moved to Crichton's body.
Tony Cox and Felix Silla both appeared in Star Wars: Episode VI - Return of the Jedi (1983) and Spaceballs (1987).
According to Shgoratchx! (1981), the robots Twiki and Crichton are programmed by Isaac Asimov's three laws of Robotics. When they are reactivated after repairs, they quote the laws and a brief history of the laws' origin.