I've read reviews where the reviewer has castigated this novel as "the perfect specimen of the Nietzschean overman who renounces the world." Others have said this book is blatantly anti-bourgeoisie as well. Such comments only reveal the misunderstanding of what Hesse was attempting to convey in this novel.
First I should point out that Nietzsche did not renounce the world at all. In some sense Hesse was heavily influenced by Nietzsche and so in order to understand something of this book it might be helpful to have read a little bit of Nietzsche himself. Unlike his predecessor Schopenhauer (another great philosopher), Nietzsche did not condemn the world. What Nietzsche really condemned was the current state of things (rampant nationalism, anti-semitism, Bolshevism, and materialism etc.) and the mentalities that produced them (racism, narrow-mindedness, complacency, and absolute religious convictions) when he scathingly criticized the 'majority', insofar as the majority embraced these doctrines. Hesse, like Nietzsche, is a 'Yes-Saying' man (Yes-saying to the world that is) and that is manifested in this novel. Obviously Hesse believed in progress and had much hope for humanity. Perhaps those who have charged the author with such nihilistic sentiments have not read further than the first half of the book and have only read the despair that Harry later transcends. This book isn't going to root out and remove suffering altogether but enough so that it isn't so overwelming that one gives up on life. As Hesse wrote, "But I would be happy if many of them were to realize that the story of the Steppenwolf pictures a disease and crisis-but not one leading to death and destruction, on the contrary: to healing."
This book is neither anti-bourgeois as Harry's deep seated contempt for the bourgeois life and its complacency climaxes in his realization that he has for so long denied and hated the bourgeois tendencies in himself and that for his entire life he has made the mistake (this is where eastern mysticism comes in and the effects of western Christianity are hung up- eg. the idea of duality and of an enduring self) of devising and contrasting two sides of himself (The sensible and reasonable man contrased with the wild and passionate wolf) when in reality he was made up of many 'selfs' that formed who he was as a man and the realization that his own false conception of such dualities only caused him more angst than was necessary. In the end Harry learns the greatest lesson; that life is both tragic and comedic and one must learn not only how to be serious but to laugh at oneself. In this respect one can see how Harry is symbolic for many things beyond himself as a man.
I will not summarize this book as that has been done numerous times already by reviewers, but after reading Siddarthra and Narcissus and Goldmund, I must say this is my favorite novel from Hesse thus far. In my book he's up there with other literary geniuses such as Goethe, Camus, Kafka, Huxley, and Orwell.
Certainly this book will attract the angst filled seekers of happiness, those who are attracted to the religions of Hindiusm and Buddhism (consider this book the nourishment that will help unfold your petal of wisdom), and free-thinkers by virtue of their conviction to always challenge reality. Even if you disagree with Hesse's sentiments you can't deny the power of his prose.