Initially, Herbert White has a playful, humorous attitude toward the monkey's paw. This is shown through Herbert's reaction when the sergeant-major tells the family about the fakir's spell, which gives three men three wishes:
“Well, why don’t you have three, sir?” said Herbert White, cleverly.
In addition, Herbert is the first one to suggest that the family use the monkey's paw to make three wishes. In fact, he believes that the monkey's paw can make the family "rich, and famous, and happy." For Herbert, the monkey's paw presents an opportunity for the family to change their fortunes. As a result, he suggests to his father that he make a wish for £200, to see if the paw really works.
Moreover, as he goes up to bed, he jokes with his father that the £200 will appear in his bed in the middle of the night. He further jokes that something evil will be sitting on the wardrobe watching his father. Herbert's attitude, is, therefore, very playful and not at all serious.
In an ironic twist, however, his father does receive the £200 that he wished for. It is Herbert's death in an accident at work which brings them the money.