I'm a cat person, but is my cat a person cat?

I LOVE my cat; I am a cat lover, as opposed to a dog lover. It is one of the ways in which I define myself: 'I'm more of a cat person than a dog person.'

But I do often wonder if there is any objective evidence that my cat loves me.

Like many middle-aged couples whose children have left home, my partner and I attribute strong views and an inner life to our cat. If it is true that a family pet embodies the family's collective persona, our cat provides a coded way of talking about ourselves.

'She doesn't look bad for her age, does she?' we say fondly, when conversation falters on the vital issues of the day. 'She can still jump up on to the side for her breakfast.'

'Just.'

The cat in question is female, ginger, 17 years old, answers to the name of Boot. She came to me as a kitten, the victim of ill- treatment. She had been thrown from a fifth-floor balcony, sustaining a broken foot and ankle, a broken jaw and a split tongue. She was on the way to the vet to be put down. My (then) 12-year- old daughter intervened, brought her home, and she's been with us ever since.

Occasionally, I persuade myself that Boot is grateful for her rescue. Realistically, I know she cannot have had the slightest understanding of what happened. One moment she was cruelly treated; the next, cruelty had been replaced by kindness.

She rewarded this kindness with three litters of ginger kittens (yes, I know, clever her: it is rare for a ginger female to be fertile) until we ran out of friends who might want a kitten now or in the foreseeable future, and the vet put a stop to her exuberant fertility.

Boot, 15 years later, has outlived all known offspring. She herself is in remarkably good nick - as well she might be, given the amount of attention we lavish on her. She looks moderately alert if you say 'Boot]' in her special voice, but she reacts in just the same way to any other word, provided the intonation is right. She comes when called, as long as it is meal time.

She is unlikely to die a natural death, living as she does on the fourth floor, remote from illness, predators, rivals, cars and cat fleas. In the end, we shall probably ask the vet to give her a fatal injection. We shall tell ourselves it's kinder. We love her and will be devastated when she dies.

Yesterday at breakfast we were discussing whether she loves us. That she needs us goes without saying. She would soon die of hunger and thirst if we ceased to supply her with food and milk and water. She seems to be aware of this, hence the affection at meal times.

These mewings and coilings and long, green-eyed looks are not love, however; they are feline manipulation. Similarly, when she sits beside us or on our laps she is manifesting a desire for warmth and comfort and only then, possibly, affection. She purrs when stroked, but that is a reflex response, not proof of love.

What evidence is there that my cat loves me, rather than just exploits me? Let me count the ways. She shows little inclination to tolerate anyone else, though she makes an exception for Tony, my partner, to whom after two intensely jealous years she capitulated.

The only evidence I can find of disinterested affection is her apparent preference for being in the same room as us.

This leads her into embarrassing situations. If I go down to the study (to send a fax, say, or look something up) she will wait a couple of minutes for dignity's sake and then follow me down. As often as not, she will encounter me emerging from the study, the fax sent, the fact checked. This obliges her to spend a few minutes in the study, staring intently out of the window as though that had been her motive all along, before returning to sit beside me again.

I can see no reason for this sequence except that she likes my company. Is that love? It'll do.