Environmental Conflict
The world of Klara and the Sun features Artificial Intelligence, or A.I., technology as a normal aspect of daily life. The novel's narrator and main character, Klara, is an Artifical Friend that humanity developed to help contend with the changing, competitive world. While the creation of beings like Klara may be positive, the development of technology such as the Cootings machine—portrayed consistently as a negative piece of technology that nobody likes, which spouts smoke and darkens the sky—shows how technological developments can also result in negative inventions. However, the fact that nobody really takes action against any of these developments, good or bad, shows how people in this society have become resigned to technology of any kind being in their lives.
Ironically, it is Klara who is the most attuned to the environment, most likely due to the combination of her reception of nourishment from the Sun and her incredible perception skills. She is portrayed as having the tightest bonds to the environment, and so it makes sense that she would be the character to destroy the Cootings machine. While many applaud her work, the broken Cootings machine is replaced by an even larger version—showing how technology has become a superpower of its own. This hints at how issues posed by human activity, such as technological developments and pollution, have become so formidable that those who prioritize nature face a tough struggle if they wish to achieve their ends. Despite this, Ishiguro shows that it's not impossible to win this struggle. While it's not clear if the sun really is what cured Josie at the end of the novel, the way in which Klara unites her connections to the environment with her love for another highlight how it is better to protect the environment while we are still able to do so.
Intelligence (And Its Repercussions)
In the world of Klara and the Sun, intelligence is valued above anything else. From an early age, children in the world of Klara and the Sun are given certain special abilities through genetic enhancement, called "lifting," to become more intelligent. However, this can only be done through a great amount of wealth, and the cost is not only financial—children can suffer physically and/or mentally as a result of "lifting," as shown when Josie nearly succumbs to a life-threatening illness. This forces the reader to ask if it is truly worth it to undergo such operations under social pressures—many wealthy children are "lifted" in this society, proving their families' value within the social hierarchy—or if it is better not to prioritize intelligence so much.
As a result of people's emphasis on intelligence, intelligence becomes a means to strengthen social boundaries and divisions. As aforementioned, many wealthy children are "lifted" because it is a social status, despite the potential risks. On the other hand, it is still possible to be naturally intelligent in this world: Rick, Josie's friend, is incredibly clever, but the only problem is that he doesn't have the finances to attend a top university. This indicates how the society of Klara and the Sun is not the meritocracy it presents itself to be, and is instead rooted in class divisions—which are reinforced by the growing numbers of intelligent members in the higher tiers because of "lifting."
In Klara and the Sun, the concept of intelligence comes under close scrutiny as a warning to the reader that though it can be used positively, too much prioritization of intelligence can result in dire consequences for the individual as well as society as a whole.
Love
Love is what unites all the characters in Klara and the Sun. Josie's emerging love for Klara when she sees her in the shop window is what leads to their relationship that helps them through the trials they face later in the novel; Josie's parents, Rick, and Klara all love Josie and do not want her to die, which becomes the main conflict of the novel. The Artificial Friends' worst fears is revealed when Josie spots a Boy AF following his girl human, who doesn't let him walk with her and instead ignores him—showing that her love for him has faded away, and as a result the Boy AF has lost one of his primary functions. Through these relationships, love in Klara and the Sun is shown to transcend humans and be felt even by robots, often characterized in other literature and media as cold, logical beings coded to respond in a limited range of particular ways. In Klara and the Sun, this stereotype is challenged with the love felt between both humans and robots.
Additionally, love is shown to be an experience unique to individuals. When Josie grows closer and closer to dying, it is revealed that her mother's plan is that if Josie dies, Klara will take on the likeness of Josie and imitate her so that life can go on as if Josie has lived. This is a question central to the novel: even if Klara does this, will it be successful? She is not Josie, so will the others be able to simply transfer their love for the real Josie to a facsimile of her? In other words, can love be created artificially, like a machine? While such questions are not completely resolved, by the end of the novel, it is clear that love is a central experience to sentient beings and what ultimately makes life worth living.
Faith
The only person who has religious affiliations in Klara and the Sun isn't a person—it's Klara, an Artificial Friend and robot. She has no concept of religion, and sees the sun as a deity based on the misconception that just because robots receive nourishment from the sun, so must humans. However, she is the only character to have faith that a larger entity will help Josie, who is gravely ill, and executes quiet rituals to the Sun—which she views as a god—in the hopes that it will cure Josie. Here, faith is what provides the foundation for hope in a future good, and the ability to move forward in the face of conflict.
Faith is not only defined as "religion," but also takes on the form of faith in others. Rick, despite wanting to be an engineer and having a very logical mindset, overlooks his idea that Klara's rituals are just superstitions and supports her actions even when he does not fully understand what she is doing. He keeps her secret for her out of their mutual friendship, and his faith that her faith will make Josie well again. As a result, faith in others and not just faith in a larger entity is what helps propel the characters' relationships into a brighter future.
In Klara and the Sun, faith is more about how it gives one the hope and strength to continue, than it is about believing in something "correctly," or if one is justified in that belief. This links it back to the theme of love, because more than anything, the faith shown in the novel is grounded in a deep form of love that does not allow the characters to give up on one another.
Loneliness
In Klara and the Sun, loneliness is felt by most, if not all, the characters. Children now need Artifical Friends so that they don't lose out on the social interactions necessary to their growth. Parents hold socialization events so that their children are forced to interact with one another, instead of staying alone at home all the time. Human interactions feel forced or practiced, and the few real ones—for instance, Josie and Rick's relationship—is often discouraged due to distances caused by class divisions.
In contrast, the end of the novel shows Klara alone at a kind of nursing home for retired robots, but she does not seem to feel lonely. She greets the clerk at her old store cheerfully, and they have one nice, final conservation together. The fact that Klara does not really feel sad and is enriched by her memories of her relationships shows that, at least in Klara and the Sun, there is a clear distinction between being lonely and being alone, and how this difference is defined by the bonds one has created with others.
