There’s a story about a science teacher who was trying to teach a group of fourth year boys. He stood at the front of the classroom explaining the subject when he noticed there was a boy at the back not paying attention. He stopped what he was saying and said to the boy, ‘what’s electricity?’

The boy realised he had been caught out. He looked around at the rest of the class, but no-one was going to give him an answer. ‘What’s electricity?’

What was he going to say?

He looked at the teacher and said, ‘Sir, I knew, but I’ve forgotten’.

The teacher looked at the rest of the class and said, ‘Do you hear that? The only person in the history of the whole world who ever knew what electricity was has forgotten’.

There was always a nagging sympathy for the boy, how often have there been moments when there were thoughts at the corner of the mind, words on the tip of the tongue, something almost understood? Perhaps not an explanation of electricity, but answers to other questions.

Perhaps brilliance lies not so much in the capacity for understanding, as in the capacity for the mental filing and retrieval of information. Attending an Open University psychology lecture once, the lecturer was talking about memory. He suggested that it might be possible that the brain retained everything we ever heard. (This had seemed doubtful at the time, I couldn’t recall what the lecturer had said in his previous point). The problem, he said, was in recalling the information from the depths of the memory

Wanting clarification, I asked him a silly question. ‘Does this mean that if I listened to the football results on the radio in October 1974, somewhere in the depths of may brain are all of West Ham’s scores?’

‘That’s the theory’, he said.

Imagine if it was possible to so effectively file everything we heard, or saw, or read, that all the information from disparate sources was gathered together in the mind in appropriate sections and sub-sections, and that it was then possible to efficiently recall that information in a structured and logical way. Of course, understanding would be needed to analyse the material and construct arguments, but a case resting on a mass of evidence tends to be far more convincing than one resting on little more than verbal brilliance.

The problem for schoolboys generally may not be so much the lack of a capacity to understand as the lack of capacity to remember; a thought which arises from the fact that starting to write this piece with the story about the electricity, I completely forgot what it was I had originally intended to say.