Showboat World is a 1975 novel by Jack Vance, a sequel of sorts to his early work Big Planet. The book takes place in an unspecified future when disparate groups of settlers have settled on "Big Planet", a world without metal and with low technology levels.
The book more specifically follows the career of a showboat owner named Apollon Zamp who travels along the main waterways of The Big Planet, offering a variety of entertainment to the otherwise isolated residents. Living on a world with scarce resources and different systems of morality, Apollon Zamp lives by a combination of hard work and scamming people---a hustler of sorts. What would be a series of picaresque adventures is given a frame, in the form of a combination by one of the Big Planet's many petty tyrants to present the most amusing entertainment for him. Apollon Zamp, together with pedantic museum curator Throdorus Gassoon and mysterious noblewoman Damsel Blanche-Astor decide to put on an ancient play form Earth called MacBeth and travel up the river giving one disastrous performance after another, always managing to escape struggle by a narrow margin. (Perhaps their troubles are formed because they don't know not to refer to the play by name). The conclusion of the book has a somewhat abrupt and cheerful ending.
Jack Vance is a famed science fiction writer, but until now I haven't read an entire novel by him. I have read some of his stories and novellas in Fantasy & Science Fiction. His writing is conversational, light and full of witty dialog. But beyond the style, one of the interesting things about Vance is how few Big Statements he makes in this book. The writings of Vance's more famous contemporaries, such as Isaac Asimov, Frank Herbert and Robert Heinlein were full of Big Statements, cosmic histories and all-encompassing societal studies. In this book, at least, Vance is happy to show us the life of a petty entertainer trying to survive. But the book has probably aged well because of that: while Asimov, Herbert and Heinlein come across as somewhat portentous and heavy handed, even to their fans, this book has a whimsy and cleverness to it that has not aged.