Jigdreams

Rather an odd dream about jigsaws last night, quite incoherent on waking.

I was doing a jigsaw when I suddenly came across a sort of trap, in the form of a choice between placing one piece in the position under consideration and placing another. The pieces very much of the rather odd, and yet to be reported, flavour of jigsaw 12. Chose the wrong piece and the whole jigsaw goes terribly wrong in some way, some way which I am no longer able to elaborate beyond a strong association to the face of the late Richard Briers, the bad parson of last night's 'Midsomer Murders'. The loop is closed by his murder weapon - an Indian, sabre like sword - being very similar in shape to shapes found in many of the pieces of the jigsaw, an important aspect of its oddness.

There is also a brain failing which I forgot to mention in the context of jigsaw 11. The sky being difficult, I resorted to sorting by colour - either blue or white - and then by prong configuration.  The idea is then that one soaks up the salient details of the position under consideration into the brain, then scans the pieces in the relevant heap or heaps for a match, without needing to actually try many candidates. The brain is supposed to be able to pick out, if not the right piece, at least just a small number of possibles. An example of salient details might be hole, then long section, then short section at an obtuse angle to the long section, then prong.

But it was not working very well. I found that the scan only worked if I orientated the pieces in the heap to match that of the position under consideration. The brain was unable to do the rotation for itself - something that I am sure it used to be able to manage. As a result it was questionable whether the technique was helpful at all - in the sense that just trying all the pieces in the relevant heaps might be quicker than trying to be clever about it.