How often do each of us glimpse something that instantly spins our thoughts way out of kilter?
And once that's under way how hard is it to separate our fantasy from the reality?
"The late afternoon sun was very bright and shining in through all the top floor windows of the houses, which are set below the level of the railway track. One of the houses has clearly recently been extended and has new, large windows through which I could see the most fabulous, over-large bed, with a black metal frame and brilliantly snowy-white bed-linen. The cream coloured room, flooded with sunlight, and the freshly prepared bed looked, in that short moment, like the ideal place for a fabulous afternoon and evening of long drawn out lovemaking."
The brilliance of the near to horizontally slanting rays made all but the bed itself blurry; but I knew she was standing beside it, knew she was looking through that very same window, knew she was watching how swiftly the train passed, knew that she knew I was on it - and knew that we both knew it would now not be long before we were once again united.
What I could not know, but could certainly start imagining, was what she was wearing.
Would it be that white silk nightdress? The one with the seemingly endless vee shaped insert of lace; lace that not only allowed me to see the firm inner curves of both of her beautiful breasts, but also the sweetly dimpled incurve of her navel, and even the shadowy hint of the furry softness a little way beneath it.
Or perhaps it would be that pale pink one; the one artfully constructed of layer upon layer of the finest chiffon, each layer separately all but transparent, yet all together combining to leave her curves as no more than a series of merely achingly tempting shadows.
Then of course it might be those pyjamas, the ones I had brought back for her on my last trip East. They too were of silk, but their fabric had been produced from the very finest of threads and so clung to the warm shape of her body more like a second skin than any normal garment of clothing should be able to. And its surface had been most delicately painted, by what had clearly been the most skilful and loving of hands, the colours and design chosen to highlight those very parts of a woman's body that all men most long to see, to touch, to kiss.
But then maybe she had herself recently purchased something new, something I had yet to see.
She, we, had so many choices - and that was without even considering what she might have chosen for me to change into.