the shape of sunlight and soil fertility." If food becomes more expensive, then we must change our diet: kick the addiction to cheap white meat -- chicken and pork -- which gobbles up extravagant quantities of grain. My mind tells me that we could solve the problem by adopting GM technology, which is anathema to the muck-and-mystery brigade. My conscience nags that Holden has got a point. And so, yes, it may be that I have lost the faith. I shop promiscuously. Aisles of perfectly formed, caterpillar-free cauliflowers make eyes at me. Chiller cabinets of non-organic delicacies beckon flirtatiously. I succumb. But oh my goodness, the guilt. Part of me feels that food shouldn't be this cheap, that some aspects of conventional agriculture are the equivalent of the credit boom that delivered short-term profits for the banks but ruined the economy. But no, I can't resist. Another packet of overpackaged Extra Special Parma ham (from an intensively-reared pig, probably trundled across Europe from Denmark to Emilia-Romagna) goes into the trolley. Look, there is Mario, who produced it, beaming at me from the packet. Perhaps I shall return to the organic fold one day, when I can afford it. I fear it is a question of St Augustine's prayer: Lord, make me chaste, but not yet.