Apropos of nothing in particular, gratuitously to boot, here's a picture of a fine pint of Guinness, plan view, taken on St. Patrick's day at Canberra's salubrious Irish Club.
The busy barstaff attempt to draw a shamrock in Green Goo on the head of your Guinness. As the day wears on, these designs become more abstract and creative. And indeed, I became more abstract and creative too, easing into the flow state before you can say 'Mihalyi Csikszentmihalyi'.
Somewhere in New Scientist - and I wish I could find it to wave at you Right Now - there's an article explaining how up to half a pint of beer will aid your thinking. Inspector Morse did insist that the odd pint or two was a great aid in solving crime. The effect scales badly, however…
Due to the uniquely long-lasting properties of the Guinness head, you can drink the underlying stuff and continue to meditate on the symbols up top. Intriguingly, insight seems to deepen as more of the blackstuff ends up inside, preparing one for the main lesson: as the end approaches, the most delicate of designs dissolve into chaos, instructing us thus in change, impermanence and the transience of beauty.
And yet: the promise of regeneration and renewal - as you slope off to the bar for a refill.