I have an inherent fear of snakes. Even the most innocuous of grass snakes assumes the status of an anaconda in my imagination.

As a child, I sought out the privacy of a large bush, only to discover that I had picked the very spot favoured by adders. I don’t know who was more surprised, the adders or me. It’s a testament to youthful speed and agility that I lived to tell the tale.

As a student I was once enjoying a moment of privacy in our shared house bathroom when I began to suspect I could have overdone things. The lino appeared to be moving. There was something on my foot. While I could not be certain, I was taking no chances and the sequence of events went; departure from bathroom and house followed by the securing of clothes. It turned out to be a garter snake that I had unknowingly shared several nights in front of the telly with. No one had said a word. I never went back.

On an elephant ride through the rain forest in Thailand, the Mahout thought it would be amusing to give us a close up view of long black snakes hanging from the tree. In an effort to keep me calm, my companion counselled against this course. The Mahout, who had huge pupils shimmering like saucers, was only encouraged. I held on tight as a snake brushed past me. I never saw it until it was literally upon me. My companion had to hold me down.

When I was in Delhi I ambled across a very pretty court yard, narrowly missing a collision with a small unimposing man sitting cross legged on the floor. What I didn’t spot, but my friend did, was the cobra in a basket in front of him. Knowing how scared I would be, he never said a word until after we had left.

At a picnic table outside Cairns, the then sixteen-year-old son said to me, “whatever you do, don’t turn round.” I turned round to find myself nose to nose with an enormous python. On the upside, it was good to know that I had lost none of the agility that had saved me from the adders. In a seamless maneuverer, I vaulted the picnic table, sweeping away a picnic for six. I took out at least one of the small children sharing the table with us before ending up face down on the ground.

Amidst the crying and gasping, hysterical laughter, cheering and clapping all around me, the Son was not sympathetic. “I told you not to turn round.”

Recently I fear I spent a night in close proximity to a snake in a vivarium no one told me about. I enjoyed a perfectly good dinner and nights slight in ignorance of this fact. Had I have known, I should have immediately left. Knowing it now, I put my trust in my friends coming clean next time around.

It is one of the quirks of sight loss, that in trying to make sense of the visual world, and being hard wired to spot danger, I cannot help but let my initial assessment of the situation scream a warning. My initial assessment is not always the most reliable. In the rolodex of possibilities that runs through my mind, and on the limited visual image available, first thoughts don’t always turn out to be right. A flashing thought that I am standing next to a bear on the Northern line sends my stomach into a lurch. Fear is quickly tempered by a rationalisation that this is a person in a fur coat.

When the Lady in the Van spotted a Boer constrictor on Parkway, everyone laughed, but she turned out to be right. You can never be too careful.