Jackson Galaxy says that two cats are better than one if you are adopting from a shelter. That’s a good reason but I’m not going to count it as one of the six on this page. However, he should know.
The first reason, and this is a good one, is that it generally works well. I can say that with some confidence because of a study that was carried out in 1999 by Barry and Cromwell-Davis. They checked out the behaviour of cats in 60 homes in which there were two cats. They observed male-male, male-female and female-female relationships. Each pair was observed for 10 hours and there was a total of 600 hours of observation. All the cats were neutered and they were all confined to the indoors. In general, the researchers found a higher degree of friendship and companionship than they had expected. They observed 68 instances of aggression. These depended upon the individual character of the cats rather than their gender, age or other factors.
The longer the relationship, the better they got along. In other words there was less aggression in long-standing relationships. The cats spent an average of 40% of the time within 3 m of each other despite the homes being large enough to keep their distance. Male-male pairs spent more time in close proximity than other pairs. By close proximity they mean under 1 m in distance. Clearly a lot of the time they spent in contact with each other.
There was a wide range of friendly behaviours noted including sniffing each other, grooming each other and rubbing against each other. In short, the cats behaved as if they were social animals rather than independent asocial animals which is the general impression that people have of domestic cats. Two-cat homes work well, generally, all things being equal.
The experts are always harping on about cat owners not playing enough with their cats. There are various reasons why people don’t play with their cats but I think we can say with confidence that there is not enough of it for the average domestic cat. When there are two cats in the household who get along they can play with each other which takes away some of the responsibilities of a concerned cat guardian.
It is said that bored cats can become mischievous cats and mischievous cats can cause problems or engage in what is euphemistically called “bad behaviour”. I think their behaviour is behaviour that people don’t like rather than bad behaviour per se but that’s just my thought about it. The argument is, however, that where there are two cats they are better behaved. This must depend upon the age of the cats because kittens like to race around in pairs.
Where possible two cats should be adopted from an animal shelter at the same time. It is not uncommon that two rescued cats are very close to each other and therefore they should be rehomed together. This is advantageous from the simple perspective that a person is saving the lives of two cats rather than one.
When two cats play with each other or interact with each other generally they will be expending energy and burning calories which must be a good thing because all of us in the cat world have heard about the epidemic of feline obesity which runs in parallel to a certain extent with human obesity. Two cats living together helps to reduce the risk of obesity.
In the modern world a lot of cat owners have busy lives. They’re are out of the home most of the day. Under these circumstances a single cat may suffer from separation anxiety and be lonely. It’s logical and commonsense that a second cat will help to remove this emotion and stress.
P.S. People should adopt new cats into a home where there are existing cats with care and caution. I think there is a difference between 2 cat homes and multicat homes where there are considerably more than 2 cats. The latter scenario can lead to stress in one or two cats.
Some pages on multicat homes
How do 25-30 pound Maine Coon cats get on with normally sized 10 pound domestic cats? Do they take advantage of their size?