Rational or what?
I rarely applaud much at events, and often not at all.
There is no great principle at work here. Simply, I have always understood that one claps the hands together to signal appreciation, pleasure, perhaps agreement, in order to convey one's feelings to the performer, and does so in proportion to how strongly one feels. How long this is continued, I have understood, indicates the degree of one's appreciation.
I never applaud films or other recorded performances because the feedback element is absent. And I was not brought up to applaud professional or academic presentations – as just not appropriate to such occasions, except perhaps in the case of personal tributes.
I realise that acting as I do in this respect may make me stand out, appear odd, or worse.
I am therefore pleased (cue for applause?) to wake this morning to BBC World Service's report of one of those jolly little social-psychological studies involving undergraduates:
Oh well, now for the morning's regular 'real news', like dirty doings in our world-famous National Health Service, dodgy bankers, Syria, the busy world of the 'international community', the economy, the weather etc.
Morelle, R. Clapping reveals applause is a 'social contagion', BBC News, 19 June
Includes nice onwards links, though the original report is not available on line, not yet anyway.