The most plausible justification for higher taxes on automobile fuel is that fuel consumption harms the environment and thus adds to the costs of the traffic congestion. But the fact that burning fuel creates these “negative externalities” does not imply that no tax on fuel could ever be too high. Economics is precise about the tax that should, in principle, be levied to deal with negative externalities: the tax on a liter of the fuel should be equal to the harm caused by using a liter of fuel. If the tax is more than that, its costs (including the inconvenience to those who would rather have used their cars) will exceed its benefits(including any reduction in congestion and pollution).
我认为这句话的意思是,燃烧煤炭有坏处,但这不代表就可以无限制的在fuel上征税。(no tax on fuel could ever be too high, 我的解拆是先看tax on fuel is too high,然后前面加上no,就是说没有什么税加在fuel上是太高了的,就是很高很高的税是可以的,然后这句话前面还有句doesn't mean,就是说加粗那句话是错的,也就是说,不是越高越好没有限制)
这段话总的来说就是在讲有的时候高税是错的,还是要保持平衡(the tax on a liter of the fuel should be equal to the harm caused by using a liter of fuel)
其实理解这个也可以想对富人的税收,许多人觉得他们钱多所以收税越高越好,no tax on the rich could ever be too high:),但实际上如果对富人或者资产多的企业税收过重,会影响国家经济,带来不良影响,因此虽然他们很有钱,也不代表说对他们收的税就可以没有限制。
第一句说的是高税的justification是fuel consumption有害,第二句说的是但是the fact that burning fuel creates these "negative ..." does not imply。。,这前半句在说“就算burning fuel是坏的,也不能说明。。。@¥^@#^@%¥”,是要推翻第一句的justification,第三句第四句说的是税收其实应该平衡,所以可以推断出第二句说的是就算burning fuel是坏的也不能justify高税收(而事实上税收应该平衡不应过高)。