“So terrified was he [my eldest brother] of being caught, by chance, in a false statement, that as a small boy he acquired the habit of adding ‘perhaps’ to everything he said. ‘Is that you Harry?’ Mama might call from the drawing-room. ‘Yes, Mama - perhaps.’ ‘Are you going upstairs?’ ‘Yes, perhaps.’”
The above is a quote from Eleanor Farjeon’s ‘A Nursery in the Nineties’ – an excerpt included in ‘The Uses of Argument’, by Stephen Toulmin. He used the term “non-committal façons de parler” in his book and that term stuck with me through the years.