The mood organ is a futuristic technology that contributes to the general atmosphere of the book, but it is also satirical. The satire becomes especially clear in Chapter 22, when Iran sits at home waiting to see if Rick will come home:
If Rick were here, she thought, he’d get me to dial 3 and that way I’d find myself wanting to dial something important, ebullient joy or if not that then possibly an 888, the desire to watch TV no matter what’s on it. I wonder what is on it, she thought. And then she wondered again where Rick had gone. He may be coming back, and on the other hand he may not be, she said to herself, and felt her bones within her shrink with age.
Iran has a mood organ at her disposal with at least 888 channels. She can make herself feel any number of highly specific feelings, including "the desire to watch TV no matter what's on it." The reader is likely familiar with this desire, as well as the related feeling of frustration at flipping through channels and being unable to decide what to watch. It seems odd and almost comical to engineer this exact feeling. For that matter, it seems even more bizarre to simply turn a dial to feel "ebullient joy." Joy that boils over like this is rare and precious, and it usually comes as a natural reaction to something truly wonderful. It would be out of place in this moment, when Iran is sitting listlessly and uncertainly on the couch.
In the 1960s, when Dick wrote this novel, antidepressants were becoming more popular, as were other mood-altering drugs, like psychedelics. The mood organ is a highly exaggerated form of a drug regimen. The novel does not outright reject the idea that these substances might be helpful; in fact, in the bleak setting of the novel, the mood organ literally allows Rick Deckard to get up in the morning. It also allows Iran to access gloomier feelings when she decides she wants to process the trauma of surviving World War Terminus. At the same time, the intense specificity and huge range of choices on the mood organ's dial beg the question of when the ability to shift moods on a dime might become more of a hindrance than a help. On a practical level, the mood organ must be an enormous and encumbering piece of machinery if its dial can fit so many settings. On a spiritual level, Iran raises the concern early on that a constantly modulated mood is preventing her from responding naturally to her environment. For example, has she ever experienced naturally-occurring "ebullient joy?" Would she feel a difference between "real" and artificial joy? In this scene, she understandably experiences choice paralysis. She is not in the mood to pick a mood.