But it raises several interesting questions. For example, is it truthful? As a teenager and young adult, I used to cycle around London a lot, and I navigated by a mental tube map which I carried in my head. It worked: but it did take me on some strange routes at times; and it was certainly very misleading if one thought that the stations were equi-distant, as they are on the map. Cycling out to Watford or Epping soon disabused one of that illusion.
But of course the map is not designed to designate distance (nor to be used by cyclists). It conveys the information it is designed to convey very accurately: which lines stop at which stations, in which order; and where connections may be made.
Which reminded me of, say, Fundamentalists (and atheists, come to that) reading Genesis. It teaches precisely what it is intended to teach, but reading it in the wrong way may take you round the houses...
It is very popular in some circles to parrot: the Map is not the Territory; a mantra made popular by the pseudo-psychology known as NLP. At one level this is a truism: of course a representation is not the thing it represents. However, frequently people make the illogical leap to: therefore, as we all have different maps in our head, there is no such thing as objective reality. Yet somehow, when I emerge from Oxford Circus tube station, there is Oxford Circus: and it is when you do, too. And we know, as a matter of everyday experience, that we rely on objective reality being there, and on maps of various kinds as guides to it.
Thus the questions to ask about any map, whether a tube map, Wainwright's sketches of the Lakeland Fells, or the Ordnance Survey, is firstly, what are they trying to convey; and secondly, how well do they do that. And the same applies to the religious and philosophical maps which we use to make sense of life.
But, of course, the real reason for this post was an excuse to link to the sounds of my youth, here: