However, it is more likely that the sentence refers to the actions of the cat rather than to the actions of a human being on them; and an indication of what the original phrase may have meant is found in George Wither`s book A Collection of Emblems, Ancient and Modern where he writes about the proverbial cat hunt: “He can`t just shoot them / but hee must also play / and sport his nostalgic prisoners live”.” So if we`re “careful” to worry and take the time to get excited about something, instead of just continuing and taking decisive action, then what the cat can “kill” is not killing its prey when it was lucky. And then maybe either to be killed by hunger (because his dinner disappears) or to be evicted by his owner, dissatisfied with his ability to mousing? “All-Gone” was already in the poor mouse`s mouth, and she had barely said it before the cat jumped on her and swallowed it. The real proverb is: “Curiosity killed the cat, but satisfaction brought him back.” Again, the meaning of this sentence is actually the opposite of what people believe it means. The phrase itself encourages people to be curious, especially when it comes to learning new skills and ideas. While the first half of the sentence warns not to ask too many questions, the second part indicates that there are not too many questions. In both cases, “care” means “concern” or “concern,” as is often the case in Shakespeare`s plays of the time (Compare the opening lines of King Henry IV of 1st Henry IV: “As shaken as we are, wan carefully”). The meaning is clearly different here: it is the worry or sorrow that killed the cat, not his nose while chewing. Of course, it is possible that it is not the care of the cat that is the cause of the problem, but that of the human owner: in other words, excessive anxiety about something can cause you harm to your fellow human beings. But this does not come out of the phrase “care killed the cat,” and it is impossible to know a few centuries later, with certainty, what the phrase should mean.
Although cats were much infused in the Middle Ages and early modern times, not least because of their associations with witchcraft and black magic (black cats, of course), they obviously had their use to free the homes of rodents and other vermin.