I have a collection of Asimov short stories, I hadn't read in a few years, so Idecided to take a flip through it and see if I wanted to keep it, or do the "donate to the library" thing. Well, I think it's sticking around, but that's not really what I wanted to discuss.
There are certain things that keep popping up as parts of the stories. Some of them make sense, given the time period the stories were written in, such as a idea that the Atomic Age is the start of a new era for humanity (there are more than a couple of stories where the years have been renumbered to start from the a-bombs being dropped). There are others I'm less certain as to their frequent use, and one of those is the collective mind race. In various stories, humans come face-to-face with a species of intelligent life that have collective intelligence. In most cases, it's similar to the Phalanx-Select we saw in Annihilation: Conquest, where individuals retain their own traits, but they're connected to a larger consciousness, which affords a certain ease of communication, and a greater sense of connectedness to those they care for. In one story, Green Patches, it seems as though an entire world is covered by a giant collective entity, one which can send various smaller parts of itself out autonomously, and disguise themselves as all manners of things, and is able to infect anything, if it chooses, be it bacteria or various multi-celled organisms.
What I find interesting is the reactions of the non-Earthlings to the situation, compared to how Earthlings react. The Earthers tend to recognize certain advantages to the collective mind approach, but aren't really interested in it because they value their individuality*. Meanwhile, the aliens, if they aren't trying to actively add humanity to their group, are horrified at the idea of each person being a separate indivudal, not connected to others. I've been trying to decide why that might be, since I don't think it's Asimov going for some "Humans are better and open-minded" approach. The best I can decide is that if a being is raised in a world where they are always in contact with everyone else, or can be so anytime they wish, they would grow accustomed to that, and the idea of being totally alone, without that immediate comfort of mental connection, would be terrifying.
Asimov deals with that sort of thing in his other works, in other ways periodically. One of the bits from his Robots series was that Detective Bailey was from Earth, where everyone lived in crowded cities underground, but he keeps being called to solve cases on Spacer worlds, where all the citizens live above ground, on sparsely populated worlds**. This confronts both parties with difficulties, as Bailey has to adjust to being in the outside world, where there are often no walss anywhere in sight, just a vast openness. Meanwhile, the Spacers, who are used to maintaining distance between themselves, have to contend with this Earthman who is used to be crammed into spaces with other people, and thinks nothing of trying to shake their hands. Everyone has to confront unfamiliar situations. The reasons humans might not be so bothered by the idea of collective intelligence*** is because humans group together frequently anyway. So it's not as completely alien of a concept, as it is in reverse to the aliens. The idea of collective minds comes up in the Foundation and Robots series as well. In the Foundation series, it's fairly overt, but in the Robots series, I felt Asimov was suggesting that when there are a large number of people together, they can have a sort of collective mind (a nicer form of mob mentality I suppose), and this was perhaps some of the groundwork for psychohistory. If humans have a vague network of collected consciousness when together, then it might be possible to predict their actions based on that, etc., etc.
I'm not certain why the idea holds such appeal for Asimov. He did write many of these stories in the post-World War 2/Cold War era, so it's possible he saw people seemingly very close to wiping themselves out, and felt a collective mind society would prevent such things. You couldn't drop bombs on those people over there, because they are part of you, it would be like dropping bombs on yourself. That could certainly hold some appeal, but I'm just speculating.
*Interestingly, Asimov will show humans developing a form of collective thought in stories that don't involve other intelligent species. It's one of those possible endpoints for us, along with moving beyond the need for physical forms, or at least being able to move without them, as mental energy.
** If I recall, there were more people on Earth than on the 50 Spacer worlds combined. One Spacer world had something along the lines of 200 people, so each person had an estate encompassing thousands of square miles.
*** Though in Green Patches the crew was less than pleased when they learned that not only had the lifeform somehow, involving spores, I imagine, impregnated all their female test animals, but all the female crew members as well.