The American Dream
To someone who has never suffered, the American Dream might seem to explain itself. Get a more luxurious life by working hard. But to Sammler, with his experience of horror and death, having been in a concentration camp during the Holocaust only decades earlier, has a different opinion. To Sammler, the American Dream is something he starts to detest, because he feels that the quest for luxury is self-defeating, and it doesn't even make people happy; it makes them miserable.
Suffering and survival
Another risk of luxury and excess that Sammler notices is that because suffering is universal, luxury actually poses a threat to survival by making people lazy and entitled. When life comes in its full glory, they won't be ready to adapt to the changes that sudden twists of fate can often bring. He knows this because he is a Holocaust survivor, and the difficulty of survival is never far from his mind. He was asked to survive a truly horrific fate, so he knows that life sometimes poses difficult challenges.
Technology and progress
The promises of progress and technology are met with scrutiny in Mr. Sammler's opinion. This is because he doesn't necessarily think that human progress is enough to really solve the problems that life can offer. In his experience, technology comes with a dark side. He knows that technology worked against his community in the Holocaust because progress brought war machines and new ways to torture the innocent. Ironically, those threats go unnoticed in the capitalistic environment he lives in.
