Prophets smite their brows in exasperation at this logic. To their minds, evaluating farming systems wholly in terms of calories produced--in terms of usable energy--is a perfect example of the flaws of reductive thinking. It does not include the costs of overfertilization, habitat loss, watershed degradation, soil erosion and compaction, and pesticide and antibiotic overuse; it doesn't account for the destruction of rural communities; it doesn't consider whether the food is tasty and nutritious. It's like evaluating automobiles entirely by their gasoline mileage, without taking into account safety, comfort, reliability, emissions, or any of the other factors that people consider when buying cars.