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Cause and effect

Let us stand up straight, step back from the yawning chasm of the absurd, shrug off the bioharness, and ponder whether there might be a better way of going about this. Perhaps the linkage between cause (calories eaten and burned) and effect (weight gained and lost) could be used to accomplish the same results without ending up as a cyberpunk centerfold.

After all, what we care about is weight, not calories. Might there be a way to extract the information we need from the weight numbers served up so easily by the scale? Indeed there is, but extracting the information we seek, calorie balance, from the confusing welter of weight measurements requires another mathematical trick borrowed, not from engineering but from the toolbox of the stock and commodity trader.

Like most attempts to characterise a complicated system by a single number, a scale throws away a great deal of the subtlety. Every morning the rubber bag sloshes over to the scale and heaves itself onto the treads with a resounding splorp. The scale responds with a number that means something or other. If only we knew what.... Over time, certainly, the scale will measure the cumulative effect of too much or too little food. But from day to day, the scale gives results that seem contradictory and confusing. We must seek the meaning hidden among the numbers and learn to sift the wisdom from the weight.

By John Walker