Day30 Many farmers who invested in the equipment needed to make the switch from synthetic to organic fertilizers and pesticides feel

The following was excerpted from the speech of a spokesperson for Synthetic Farm Products，Inc.：

“Many farmers who invested in the equipment needed to make the switch from synthetic to organic fertilizers and pesticides feel that it would be too expensive to resume synthetic farming at this point.But studies of farmers who switched to organic farming last year indicate that their current crop yields are lower.Hence their purchase of organic farming equipment，a relatively minor investment compared to the losses that would result from continued lower crop yields，cannot justify persisting on an unwise course.And the choice to farm organically is？nancially unwise，given that it was motivated by environmental rather than economic concerns.”

Discuss how well reasoned you find this argument.In your discussion be sure to analyze the line of reasoning and the use of evidence in the argument.For example，you may need to consider what questionable assumptions underlie the thinking and what alternative explanations or counterexamples might weaken the conclusion.You can also discuss what sort of evidence would strengthen or refute the argument，what changes in the argument would make it more logically sound，and what，if anything，would help you better evaluate its conclusion.

文勇五问：

（1）本题中，事实是什么？结论是什么？“But studies of farmers who switched to organic farming last year indicate that their current crop yields are lower.”和“it was motivated by environmental rather than economic concerns.”是事实，“Hence their purchase of organic farming equipment，a relatively minor investment compared to the losses that would result from continued lower crop yields，cannot justify persisting on an unwise course.”是结论，值得反驳吗？同学们应该注意这些话是来自什么人，这将有利于你了解本段的中心思想。本段是一名合成类农耕产品生产公司的发言人所做的演讲，这个人当然认为合成的肥料和农药会更好。

（2）一份跨度为一年的调研结果一定是具有普遍性的吗？近一年如此，过去就一定如此吗？以后就一定如此吗？这里是否犯了时间轴论证的错误？

（3）肥料和农药有机与否是决定产量的所有要素吗？如果不是，影响产量的要素还有哪些？你能罗列出一到两个其他可能的要素吗？例如：种子质量的高低，气候的好坏。而这是否意味着转向有机肥料和有机农药可能并非造成产量降低的唯一原因，可能并非重要的原因，甚至可能并非其原因？即便产量真的是因为有机肥料和有机农药变低了，有没有可能是因为农民本身首次接触、不熟悉而使用不当呢？

（4）产量变低，就一定意味着收入也变低吗？产量有没有可能并非唯一左右利润的因素？还有哪些可能的影响要素？例如：市场需求，农作物单价。

（5）环保和经济利益一定是相排斥的吗？可以仅凭一件事是环保的，就简单地判定它经济效益低吗？你能想到一到两个反例吗？例如：农家乐，生态养殖。

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