“Believe me, my young friend, there is nothing—absolute nothing—half so much worth doing as simply messing about in boats.”
Rat expresses exuberant delight in a simple shared activity, valuing absorbed enjoyment of the moment over a more utilitarian measure of what is worth doing.
Source details
The Wind in the Willows, Chapter I, “The River Bank,” Project Gutenberg #27805. Water Rat tells Mole that nothing is half so worth doing as messing about in boats during their first excursion, then immediately crashes into the bank while daydreaming. The line is enthusiastic comic fictional dialogue, not a universal prescription about leisure or life priorities.