"Why on earth do you climb mountains?" People ask me so often that the question now rings unspoken in my ears. I look at my shoes or out of the window and wonder why I cannot reply. Only today, sitting here while the rain falls, do I appreciate the reason for my inability to explain: now is afterwards, and so my hunger has gone. Today a photograph of a mountain leads my practiced eye to pick out a route, but there is no quickening of my heart as I imagine climbing the steep ice-face.

Comfortably alive and back in Australia, I ask myself why I spent two months of my life risking storms, rockfalls and avalanches while, on the Nepalese side of the mountain, five people from three expeditions died attempting the same feat. The secret of survival is to be able to judge precisely what one's limits are, and to have the determination and discipline to push oneself that far and no further. The temptation to reach just a little beyond one's abilty is great, but the penalty is final. Though I shall never see the summit other than through the eyes and hearts of Tim and Greg, I know that no view is worth that price.

The history books will remember our climb because two of our team stood on the top of the world. As with every expedition our overt goal was to reach the summit. Yet as each climb progresses I realise that it is not the summit that brings me to the Himalaya but to relearn the value and beauty of existence. Not only my existence, but that of the mountains, the sky, the friendship with my companions. But those rewards do not come from simply looking at the mountains. One must accept their challenge and try to touch their peaks. During the attempt, danger and hardship strip away all pretence and self-delusion. And the realisation grows that the only thing which keeps one alive is the strength of one's spirit.

When I have the time to be alone with my thoughts I can understand why I climb. But what can I say to the person who expects the answer in a single phrase? How do I tell someone who expects me to speak of fame and glory that it is really a trip into myself? How do I explain that sometimes there needs to be more to life than comfort and pleasure, that fear and suffering can reveal another dimension? And, hardest of all, how do I explain the reason for two deaths which in no way seem warranted?

Less than a week after the first Australians trod Everest's summit Craig Nottle and Fred From fell to their deaths from high on the West Ridge. As we left the mountain we had hoped that their expedition would echo our success. Now the echo rings hollow and horrific.

The mountain had cast the same spell on climbers from both teams. It had given existence and purpose. At the time when life meant most it was taken away. In its place is a vacuum and the unforgettable grief of loved ones who stayed at home. For Fred and Craig life was not muffled by fear but enhanced by it. Their final expedition gave them feelings and experiences of an intensity that few people who live to three times their age will know.

High on Everest, the line between success and tragic failure is very fine. As it was, just three of our team of five climbed the mountain (Andy will not be recorded in the statistics of Summiteers but, to our minds, fifty metres from the top of the 8848-metre peak is good enough) and we all survived. The loss of Andy's fingers seriously mars our triumph, and shows again just how small are the margins between the completely unscathed, the incapacitated and the dead.

So I feel like a survivor. The clearest view in the world is when your head is on the block, and once your head has been there the view stays in your mind for a long time. Friendships are deeper, the sunshine warmer, there is value in everything. As I sit here the rain is not spoiling the weekend but dancing across the road to nourish the grass and shrubs in the park. Being alive has never felt so good, though all I do is sit and watch the rain.

Lincoln Hall, Manly, 26 October 1984