While working in his lab one day, Martin accidently stumbles upon something that can kill harmful bacteria in the human body. He's not even sure what the thing is—an enzyme, an organism, or a virus—so he decides to call it the "X Principle." And the more he tests this principle, the more he realizes that:
What the X Principle was—chemical or germ—he could not determine, but certainly the original Principle flourished. (28.2.13)
It's clear that this new discovery could wipe out some serious diseases and make Martin famous. But he stays true to his scientific principles and decides not to publish anything until he's spent another year or two running tests. Gottlieb approves of Martin waiting to publish his findings and suggests new angles and approaches that Martin might take in his scientific inquiry. Their relationship is exemplified in this situation: Gottlieb's stringent scientific standards make Martin strive for excellence.
Unfortunately, Martin exhausts himself by hitting the lab around the clock and needs to rest. His period of rest costs him some fame and glory, as it allows another scientist time to discover the same thing and publish on it. As Max Gottlieb informs Martin,
"D'Hérelle of the Pasteur Institute has just now published in the Comptes Rendus, Académie des Sciences, a report—it is your X Principle, absolute." (29.1.69)
Dagnabbit! If only Martin hadn't rested! If only he had been able to work 24/7! Stupid Martin!
Of course, the sentences above are dripping with sarcasm: Martin had to rest, because he was having freaking sleep-deprived hallucinations. But Martin's reaction to indulging his basic human need (sleep) and losing the publishing race is one of devastation. You'd think that he had done something really basic and dumb, like forgetting to set his alarm clock, rather than acting in a responsible and healthy manner.
But he reacts this way because the X Principle represents Arrowsmith's total commitment to his scientific ideals. He would really rather not sleep, if it means finding scientific Truth.