Jamie recently discovered the joys of addition sums. Take two numbers and, purely by interposing the word 'plus', you can find yourself with a whole extra number, like some sort of wonderful three-for-two offer at the local shop. You can imagine how much fun he found this. For a while, it became yet another of his hobbies.
"What's one plus one?" he would demand.
"What's two plus two?"
"What's three plus three?"
And so on. And on. And on. On one occasion, interspersing a regular stream of sequential addition requests into his bath-and-bed routine, he got all the way up to "What's eighty plus eighty?" before Barry told him goodnight and switched off the lights. The next morning, Barry went in to get him up as usual and was greeted with "What's eighty-one plus eighty-one?" as soon as Jamie opened his eyes.
This could, of course, be just a mite less fascinating for Jamie's parents than it was for Jamie, and Barry – who took the brunt of it – did understandably like to place some limitations on the number of addition sums he had to answer at any one session. "Okay, Jamie," he told him on one occasion when Jamie started this, "we'll go as far as forty plus forty and then we'll stop." Jamie, accordingly, having worked his way up to forty plus forty and been given the answer, declared "And that is the end of the numbers. And now," he continued, "we will start again with some new numbers. What's forty-one plus forty-one?"