I am not in favor of that because the true cost to society of the various energy sources need to be taken into account. For example, if diesel burning causes an increase in hospitalization to the tune of hundreds of thousands of additional hospital visits, that makes my medical insurance cost more (not to mention the fact that I could be one of the people directly impacted). And how do you value a human life (especially if it's your own)? Currently these kind of societal costs are NOT built in to the cost of the fuel. And when you look at global warming, severe weather, crop failures, sea level rise and the astronomical cost to society (granted, perhaps not YOUR society but that of our children/grandchildren) well, it would be foolhardy to keep charging market rates that don't take these costs into account.