Professor Mark Solms, head of the Department of Psychology, writes of things that fade with time - like faxes and memories.

The letter in the photograph was written by hand, by my father, two days before he died. Its main purpose was to explain and justify the choices he had made which had so measurably shortened his life. He expressed a wish in the letter that my mother should re-marry (she was barely 50 when he died) and he took the opportunity to instruct her regarding some possible financial implications, if she were to take that step. It came entirely naturally to my father to issue instructions. I doubt he considered for a moment the possibility that he would not be able to enforce them from wherever it was he thought he was going.

I remember being impressed after the fact by the courage it must have taken to write the letter, and the generosity. I say after the fact because at the time of receiving the letter I didn't seriously believe he was going to die. Only afterwards I realised he had assumed the opposite. I remember him vigorously, angrily, shaking his head on his death-bed as I tried to reassure him.

Although the letter was written by hand, it was sent to me by fax. This was in the 1980s when faxes were printed on rolls of photosensitive paper, and it has faded with time. Now the letter is completely blank and I have to rely on my memory as to what it actually said. Memory is unreliable when it comes to things like this, suffused as they are with so much emotion.

Whenever I return to the place where I keep this letter, I am shocked all over again that it isn't really there. It is there but not there; erased, like my father's presence.

I took more interest in my family's history after my father's death than I did before. In so doing, I came to link this letter with a series of similar (albeit more prosaic) documents written by my ancestors over the centuries, many of them within days of their deaths - sometimes apparently just hours before. How did they know with such uncanny precision that their times had come? Did people die differently in the Middle Ages and early modern times than they do now? Or was there a family disposition to omnipotence even then? Once a Solms decides his fate, who is God to interfere?

When I look at this now blank letter, it brings another great event to my mind; an event that never really happened. After my father died, I dreamed about the letter. I dreamed that I had lost it and I was searching for it, frantically, everywhere. I needed to find it because I believed in the dream that the letter gave directions as to where my father had hidden his love. It was as concrete as that; all I needed was the directions. I knew he must have loved me. In my heart of hearts I truly did assume it. But he never really showed it. And since seeing is believing, I badly needed to find the letter.