Sirens of Titan marks the second book of Vonnegut's career. It's the book that started Vonnegut's career. While it's not the best example of Vonnegut's quirky pen, it does encapsulate his fascination with space, time travel and life's sometime cruel reality. Sirens of Titan also is a good example of Vonnegut's strengths in developing characters of less-than-heroic traits, but characters still respected for their 'oh well, let's keep trudging along' attitude.
This novel concentrates on some favorite themes of Vonnegut; those of inequality, luck, happenstance and indifference to others. The novel is very similar in terms of them and characterization to "Slaughterhouse 5" and in terms of the themes of inequality and indifference to "Player Piano".
Vonnegut was born in 1922 and so was a member of the generation that grew up in the Great Depression and entered adulthood during World War 2. I don't find it surprising then that this novel points out the degree with which luck and happenstance are behind much of the apparent success of individuals in society. people. He saw action in WW2. He saw masses of people being killed by simply being in the wrong place. He saw the indifference to life that marks war. What then is the purpose of life? Why are we alive. How do we confront the meaningless that is behind existence? In the novel, human civilization is directed by Tanfalmadorians to function as a means of sending messages to the pilot of a disabled space ship on the Saturn moon Triton. Malachi Constant is distressed whn he discovers this on Triton.
Vonnegut proposes an answer the questions in ending of the book. That is the answer of empathy and compassion to each other. Life is inherently meaningless at its base but that does not mean that it cannot be given meaning. Salo supplies Malachi Constant with a hypnotic post suggestion that gives him comfort in the final seconds of his life. Salo is a machine that the organic inhabitants of Trnfalmadore developed to find the meaning with life. When the machines found that there was no meaning, the organic Tranfalmaorians committed mass suicide by machine. Salo, the machine, found a purpose with his development of empathy and compassion by his interaction with constant on Triton
Etc. Vonnegut ends "Breakfast of Champions" with the word "ETC". which is the point of the novel Life does not have a principal character with major and minor points of description. Rather, as Vonnegut points out, it is like the chemical bond diagram of a polymer. Atoms and groups of atoms are connected and cross-connected by bonds going off in all directions without limits with no one path more important than any other. Continuations of chains are indicated with the mere word "ETC" with the metaphor showing that Breakfast of Champions does not really end but continues as does real life