Less than a week after Boris Johnson appeared to dismiss people with a low IQ, the inevitable has happened.
The mayor was faced with an impromptu intelligence test live on LBC on Tuesday morning - and flunked it.
"No-one said IQ is the only measure of ability", he spluttered after getting two questions wrong and refusing to answer a third.
Boris, whose Eton education was pointed out by a caller, said people were wilfully misconstruing what he had said, saying people at both ends of the spectrum needed to be helped.
"What I was saying is that there's too much inequality" he insisted.
WILL YOU FARE BETTER THAN THE MAYOR? (STORY CONTINUES BELOW):
A man builds a house with four sides of rectangular construction, each side having a southern exposure. A big bear comes along. What colour is the bear?
You could only build a house with 4 southern exposures at the North Pole - the only bear would be a Polar Bear. (Boris said brown)
If you take two apples away from three apples, how many apples do you have?
(Boris said one)
I went to bed at eight o'clock in the evening and wound up my clock and set the alarm to sound at nine o'clock in the morning. How many hours sleep would I get?
Answer: One hour
It is a wind up alarm clock which cannot discriminate between AM and PM. (Boris refused to answer)
David Cameron and George Osborne have distanced themselves from his comments, in the Margaret Thatcher lecture, when he noted that 16% of "our species" had an IQ below 85, and said more needed to be done for the 2% above 130.
And Nick Clegg accused him of "casual elitism" and talking about people "as if they are a breed of dogs".
Defending himself on LBC, he said: "What I was saying actually is there is too much inequality and my speech was actually a warning, as correctly reported by many newspapers, actually a warning against letting this thing go unchecked because if you look at what's happened in the last 20, 30 years there's been a widening in income between the rich and the poor, there's no question about that.
Boris also struggled to name the correct fare for a tube journey between Whitechapel and London Bridge, after TFL announced a fare increase.
There was silence on air as he appeared to rummage through paperwork before saying £6.70, which was wrong.