With that cleared up we can now freely discuss why people say that cats have nine lives. Did they really believe that cats had nine lives or was it just an expression? We can’t know for sure, though it is healthy to keep in mind that neither way must be assumed.
Why do cats have nine lives
The probable reason for this saying likely stems from the sturdiness of cats. They are agile. They react quickly and have a good sense of balance, though their most notable skill is their ability to survive falls from surprising heights.
Cats, like their ancestors millions of years ago, are tree dwelling animals that preferr high places for stalking their prey and avoiding larger animals. Such a lifestyle has significant evolutionary consequences, for example, creating animals that are good at… erm… falling down and not dying.
That is, cats who fell and died did not produce offspring; but offspring of those who fell without dying were likely to inherit characteristics that allowed them to survive:

- The Righting reflex of cats has been extensively studied and, with the invention of high-speed cameras, has been shown to be an almost artistic feat of acrobatics. Though we cannot say that cats ALWAYS land on their feet, they indeed do ALMOST always. No surprise—it helps them to survive when falling.
- Amortization of falls also helps them survive. It would be no use to land on feet if cats had legs of concrete. But what if they had legs made of springs? Then they would take most of the impact away from the body and internal organs. Cats don’t have springs, but their ability to flex their joints (and to time it extremely well) is the next best thing.
- Relatively slow maximal falling velocity (known as “terminal velocity” in physics) also contributes to how cats survive falls. Quite often extremely high falls. When a cat reaches terminal velocity, it does not really matter how long it takes to reach the ground. The basic physics supporting terminal velocity explain that large, but light objects (e.g. balloons) will fall slower than small, but heavy objects (e.g. bricks). In general, smaller mammals have slower terminal velocity, which is good for cats since they are relatively small. Of course, this relatively slow terminal velocity is useless by itself without righting reflex and soft landing.
There are enough reasons for cats to survive things that others won’t. Thus it’s easy to imagine why earlier people assumed that cats had multiple lives, even if they meant it figuratively.
Why cats have nine, but not ten lives?
Putting physics and biology aside now, where does the saying originate? We’d love to ask historians, but there are currently too many claims about the origin of this phrase.
While researching this article, we discovered many false explantions that lead to only one reliable conclusion: no one really know why cats have exactly nine lives. Most of the commonly expressed theories simply have no factual basis.
For example, many sources tie the phrase to a group of nine gods, often called the trinity of trinities, from Egyptian, Greek, and other mythologies, but there is no connection between these gods and cats. We have also heard claims that the Egyptian cat goddess, Bastet, had nine lives, which isn’t true; all gods in Egypt were immortals, which meant they had an infinite number of lives.
Nine was also a lucky number in ancient China, and cats lived well there. But again, there is no reason to claim that this is why cats have nine lives. Maybe this why there were nine rings Dante’s Hell, but who knows?
Besides, did the number have to be lucky at all?
Well, it depends on whether people considered a cats’ sturdiness a good or bad thing. That brings us to Medieval and Early Modern Europe—a place where cats, mostly for religious reasons, were not treated well, to say the least.

People burned cats at stakes, threw them off towers, and executed in several other ways during the witch hunts. This happened from the 15th to 19th centuries with a peak between 1580 and 1670.
This period strangely coincides with the repeated notions of cats having nine lives in English literature. Shakespeare’s Romeo and Juliet, Martson’s Dutch Courtesan, Butler’s Hudibras and other works from the 16th and 17th centuries mention cats having exactly nine lives.
The earliest written reference is Heywood’s Dictionary of Proverbs, which was published in 1561. It state that women have nine lives, just like cats. However, it implies that this was already an established expression: everyone knows that cats have nine lives, but hey, who knew that women have, too?
Although this theory on the origin of this phrase is more plausible than others, it still leaves us clueless about why exactly nine.
The truth is that it wasn’t always nine. Spanish and some German speaking cultures in Europe regarded it as seven. To add more controversy, Turkish and Arabic cultures say that cats have six lives. Thus, we can also ask why exactly six or seven lives? Can we know which phrase emerged first? Given the sturdiness of cats, these phrases could have been “invented” independently of each other, but we don’t know for sure.
The unnerving truth about numbers, especially one digit numbers, is that there aren’t many of them. Maybe the real reason why cats have exactly nine or seven or six lives is because there weren’t many alternatives. It couldn’t be zero or one, yet two would seem too small.