Relationships
The Professor rarely worries about the safety of the crew, viewing them as a means to an end, as evidenced in the first episode. After remarking that he was looking for a new crew for his intergalactic space ship, he was asked "What happened to your old crew?" His response was "Oh, those poor sons of a... — but that's not important! What is important is that I need a new crew!" Farnsworth's employees later discover that their predecessors died while gathering not-ordinary honey from Space Bees ("The Sting"). The Professor issues his new crew the previous crew's career chips from a manila envelope labeled "Contents Of Space Wasp's Stomach" ("Space Pilot 3000").
He frequently sends his crew on dangerous missions even when he has the foreknowledge that they will probably not make it back alive. His missions are typically those other delivery companies will not take, such as serving subpoenas to Mafia-controlled worlds or casual deliveries to virus-infested planets. Even the commercial that he had produced for his company makes several remarks to this effect, including "When other companies aren't crazy or foolhardy enough…" and "Our crew is replaceable, your package isn't."
In one episode when the crew and his ship are sent off to war, he immediately tries to hire another crew, going so far as to assign them similar character roles ('...and you'll be the foul mouthed, alcoholic robot'); he is clearly surprised to be interrupted by his old crew returning, exclaiming "Oh God, you're alive! I mean, thank God you're alive," before telling the would-be new crew to check back in a week. Even his familial relationship to Fry does not do much (if anything) to dampen the glee with which he assigns deadly delivery missions. When asked about the nature of his delivery "business", Farnsworth once clarified that he viewed his company more as "a source of cheap labor, like a family." He also frequently covets his employees' organs and blood; he once mentioned that he keeps Amy Wong around because they share a blood type. In another episode, he tries to get Hermes Conrad to kill himself in a way that would not damage his liver because "other people need it".
It is established in the episode "Mother's Day" that the Professor was once Mom's lover and employee. However, they could not maintain their relationship due to Mom's lust for power, prompting them to break up (this reportedly happened three times). When Mom takes control of all the world's robots to cause an uprising, her sons Walt, Larry, and Igner attempt to get the Professor to seduce Mom and retrieve the remote for the robots. They get back together briefly, but break up once more when Mom learns the Professor had been initially using her. It is revealed in Bender's Game that the Professor is the biological father of Mom's youngest son Igner — ironically (or not), the one that the Professor despises the most.
It was revealed in "Proposition Infinity" that he had a relationship with a 'fem-bot', though she later left him for a robot causing him to hate all robosexuals.
A creepy utilization of his body occurred in "The Prisoner of Benda", when he trades bodies with Amy. Amy then proceeds to trade bodies with Leela, causing Fry to himself trade bodies with Dr. Zoidberg. Leela used Farnsworth's body to prove that her relationship with Fry is partially physical. At dinner, Leela (in Farnsworth's Body) is disgusted by Fry (in Zoidberg's body), and vice-versa. When Leela-Farnsworth tells Fry-Zoidberg to prove his love, Fry-Zoidberg passionately kisses Leela-Farnsworth. This eventually leads to Leela-Farnsworth having Intercourse with Fry-Zoidberg. This marks the first known time Fry physically slept with a male. Mentally, however, Leela was the one who slept with Fry-Zoidberg.
As shown in "Near-Death Wish," the Professor has harbored a long-standing resentment against his parents for trying to repress his scientific curiosity when he was young. His constant experiments got him into trouble on a number of occasions, so the family moved to a farm in order to protect him. He was later committed to a mental institution, from which was later released, and does not see his parents again until the Planet Express crew finds them on the Near-Death Star and brings them to Earth. From them, the Professor learns they stayed on the farm in order to prevent their second son, Floyd, from meeting the same fate. The three reconcile and part on good terms, with the older Farnsworths returning to the Near-Death Star.
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