"There's one reason I particularly like cognitive therapy," said my psychiatrist. "Aaron T Beck, who devised it in the Sixties, is a happy, laughing, life-enhancing kind of person. Freud, on the other hand, was a miserable and gloomy old sod."

I first learnt about cognitive therapy when I was in hospital recently with depression. The idea instantly appealed. Trying to recall my inner misery with a therapist, or rediscover my repressed anger, has been useful, but cognitive therapy approached problems from the top down rather than the bottom up. It was, for me, a new way of thinking.

Concentrating on thinking, rather than feeling, is the most important aspect of cognitive therapy, the basic premise of which is that feelings are stimulated by thoughts: change the thought and you'll change the feeling, or at least alter it to a bearable level. And that doesn't mean altering the thought to something wildly positive - it's not a power-of-positive- thinking, Polyannaish therapy - it means changing it to something realistic. Thus, during cognitive therapy you're encouraged to examine the thought behind the feeling and then ask yourself whether that thought would actually stand up in a court of law. If it does, fine, but if it doesn't, which it usually doesn't, then you should substitute a thought that is more objective and truer than the original one.

Charts for cognitive therapy will read Feeling/ Situation/Thought/ Alternative Thought/ Outcome. Therefore, under Feeling you might write, "Incredibly depressed, sad, useless, pointless". Under Situation you might write, "A close friend hasn't rung back despite my leaving two messages." Examining the Thought behind all this you might see that it was, "She hasn't rung back. She doesn't care. Indeed she hates me. She's heard something I said about her. I'm hated by everyone. I have no friends. I'm a hateful person." It's quite entertaining taking these thoughts to court and bringing on the prime witnesses because it's then that you can see how completely barmy the thought was. In your cognitive court you'll find that there's a marvellous counsel for the defence who argues, "Your friend may be away. She may have forgotten. Even if she has suddenly taken against you, it doesn't mean everyone's against you. You have lots of friends. You're a reasonably popular person, in fact. On the whole you are very likeable." Because feelings are engendered by thoughts, you should find that your feelings of paranoia and anxiety do not go away completely, but at least they're lessened.

Once you've filled in your charts for a couple of weeks you'll discover Core Feelings that keep recurring - I'm terrified of being alone/being abandoned/I feel as if I'm responsible for everyone's feelings, for instance - and you then tackle the Core Feelings in much the same way, only looking back into your past to see what events triggered your having such views. Again, the Core Feelings are repeatedly tested against reality. Cognitive therapy is a way of changing your dysfunctional, or cock-eyed, thinking, into a more realistic view of life. It doesn't work miracles but I've found it an incredibly useful tool to take the edge off intolerable feelings of despair and powerlessness. Finally, most cognitive therapists only work with you for a finite amount of time - between 10 and 15 sessions. The idea is simply to give you the tools and then let you get on with itn