Who is the villain in "The Monkey's Paw" by W. W. Jacob?

From a certain point of view, I'm not sure that "The Monkey's Paw" actually has a villain, at least not one of the traditional variety. As Morris explains in the story's opening chapter, the monkey's paw was created "to show that fate ruled people's lives, and that those who interfered with it did so to their sorrow."
But while the monkey's paw has a certain malevolence about it, it's worth asking whether it exhibits any real agency or personality of its own. More than anything else, it seems like an extension of the power of fate. It is in that role, by which it cruelly punishes those who would circumvent destiny (regardless of their intentions when doing so), that the horror of the story is shaped.
The story's plot is shaped by the first wish made upon the monkey's paw, when Mr. White wishes for two hundred pounds. The monkey's paw grants the wish, but it does so through the death of his son. The two hundred dollars came as financial restitution for the family's loss. This will shape the second wish, where grief stricken, White's wife convinces him to wish their son back to life. The third wish will undo the effect of the second.
But what is driving this story's tragic progression? Is it the monkey's paw itself that is responsible, or is it merely emblematic to the real source of horror, which is the power of destiny itself, with its ability to shape the human condition?