Lose a limb and everyone you meet loses their focus. It works as surely for cats as it does for humans. Strangely, what should have been a cat becomes superseded by an event — “what happened?” The cat knows how offensive this is: sometimes, he would like to preempt the people whom he meets by widening his eyes in ill-concealed distaste, and asking “what happened to you?” But he doesn’t do any such thing. He’s only a cat (albeit the one favoured by the girl), and an idle one at that, so generally he spends his time being subjected to passive verbs — stroked, fed, carried — or else conserving his passive energy, sleeping. And in that sleep, he mostly dreams of a number whose length in letters matches its value, stride for stride.
But that missing leg continues to itch in your mind: so, yes, something did happen, and your insensitive curiousity will be rewarded to know that it was a little horrible, a little violent. Although the details will not be given outright here — or, indeed, anywhere else in Planetarium — you might in time come to learn how this cat came to be one paw short of the full quadruped; and why, if you want to keep your own limb count even, you would do well not to trail a leg over the side of a boat, or into a pond or pool, or even — if only the dangers had been clearer! — an innocent-looking goldfish bowl.