They seem to reflect the child's brain running in overdrive, expending excess energy, delighting in the limits of imagination and playing with the possibilities of the social world.
McGuinness and Robinson will undoubtedly be expending a lot of energy once the holidays are over seeking to find a compromise before Ulster Convenant day.
Still, for the elimination of doubt, and instead of expending their energies on some unwatchable head-to-head between David Cameron and Ed Miliband, couldn't the broadcasters consider a far more enticing alternative?
It is instead expending its energies on differentiating itself from them: Mr Miliband's carping about the high cost of living, with little mention of the uncompetitive, debt-laded economy underlying it, is an example of this.
On the populist right, Senators Rand Paul of Kentucky and Ted Cruz of Texas competed to sound most appalled by the idea of expending American blood or treasure in Syria.
As he has stated, "Additional units of water can always be made available by expending more resources to acquire and transport it".
Yet some are expending a disproportionate amount of blood.
"A book will use all this excess material .A book, of course, requires expending far more effort than was put into the original article, and for many ideas the effort has rapidly diminishing marginal returns.
They also don't think it matters:Political and emotional conditions do supply an understandable excuse for expending money, but not a valid one, and they do not relieve officials of the responsibility of seeking to expend public funds wisely.
To display these efforts, and manage them better, India is due this month to unveil a vaunted policy, the National Action Plan on Climate Change.It will be welcome; because many consider that India is expending even greater effort on justifying its refusal to control its emissions.
It would be a tantalising "grand bargain", particularly for America which has grown weary of expending blood and treasure in policing the region.
