How does the excerpt from chapter 5 reveal the time traveller's initial theory of the social structure that exists in the future society he visits? what is his first impression of the relationship between the eloi and the morlocks and the ways that the two races have evolved?

The Time Traveller initially assumes that human society at the time he visited only consisted of the Eloi, who had reached the pinnacle of human comfort and security. They did not lack anything materially, and for that reason, they did not seem to need qualities like curiosity, strength, and vigor. However, after encountering the Morlocks, he discovers that this society actually consists of two races—one evolving from the aristocratic class and the other evolving from the servant class.

The Time Traveller also provides a logical argument for their separate evolution based on existing social norms, which made intermarriage between the classes impossible. He believes that the master-worker relationship that existed in his time (the late Victorian period) had evolved as the two classes evolved. The upper class had become increasingly dependent on their servants for all their needs.

He sees evidence of such a trend in the Eloi, who are completely dependent on the Morlocks and lack the ability to do any kind of productive or creative work. He first believes that the Morlocks have turned into a slave class who perform all their tasks and faithfully serve their masters, even though these masters are weak, childish, and unintelligent. It is also not evident to the Time Traveller how the Morlocks benefit from their continued service, apart from having a place to stay underground. So he assumes that the Morlocks mindlessly serve their masters without any kind of gain in return, indicating that they are perfect servants. According to the Time Traveller, this relationship between the Eloi and the Morlocks is the perfect social balance.

because each is self-sufficient.  

what book are we talking about here