There was a time in my life when I became very low. It seemed as if my world was in pieces. What I was feeling was not yet clinical depression, but I had the sense that it was not far away.

I spoke to a friend who was a psychotherapist. Her reply was surprising. “I know you well enough," she said, "to know that you can cure yourself, I'll send you the literature and leave you to work out how.”

She did. I was particularly struck by those approaches called "cognitive". They suggest that what we feel is largely determined by what we think. That made sense.

We react to events as we perceive them,  not as they are in themselves. If we learn to see them differently — if we "reframe” them — we can alter our emotional reactions.

For example, I knew of people who saw themselves as failures because they were measuring themselves by the wrong yardstick.

The best antidote to this is the Chasidic story about Zusya of Hanipol. When asked why he did not behave with more dignity, he replied, "When I get to heaven, they won't ask me, ‘Zusya, why weren't  you Moses?’  They'll ask me, 'Zusya, why weren't you Zusya?’”

God does not ask us to be someone else. He asks us to be ourselves.

I found the answer. I bought a file and put in it a note of all the good things in my life. Whenever something positive happened, I kept a record of it there.

Then I put it away in a drawer. Whenever I felt low after that, I went to my study, took out the file and read it slowly, inhaling with each page.

It never failed. In the words of the Psalmist, "it restored my soul." It helped me to set the bad times in context and remember that, despite the pain, life is good. I call it my "good news file”

I have taught the principle to others and they tell me it works.