ACT写作中有几种常见的论证方式？

今天我们以ACT满分作文为例，来看看在议论文写作过程中，有几种常见的论证方式，希望同学们认真阅读，熟练掌握。

1. 因果论证

因果论证是比较常见也是大多数同学使用较多的论证方法，但是通常情况下写出的因果论证并不深入。对于多重原因的事物，如果只停留在其中的某个层面上，把它当成最终因素，论点就可能不深刻，也难以把问题说透。这样的因果论证，其说服力是有限的。

这种情况，应当一层一层地追究下去，一直到找出最终极的原因为止。一般来说，越是表层的原因，越是为大家所熟知的，其论证力也就越有限;越深层的原因，就越能说明问题的实质，就越有说服力。以旧版本满分范文里面的一段话为例：

【例1】

The replacement of humans by machines leads to the loss of value to human life, an effect that outweighs the material gains of automation. The search to find human tasks that can be performed by machines inevitably leads to comparisons between the human and the machine. If a company executive wants to see if a inventory management team can be replaced by a robotic system, he will compare the two and determine which can do a better job. When this occurs, the people on the team are evaluated not for their worth as human beings, but for their effectiveness at performing a specific function—in essence, as we would evaluate a machine. In a larger sense, when we begin to think about humans in this way, the worth of a person’s life becomes dependent on only what they can do and no longer has any intrinsic value. As Perspective One states, we begin to lose our humanity. This new mindset and way of evaluating people, though seemingly harmless in the workplace, is devastating when it begins to pervade a society. If a person is judged only on his or her capability, there is no reason for a person to remain after they have served their function. This would warrant genocide against the elderly and the disabled because their burden on society would not be made up for by any production. Although the machines may seem to only fulfill the low skill jobs at the moment, there is no barrier to prevent the machines from replacing more. As the machines increase in intelligence, they will replace any tasks done by humans and render us unnecessary and worthless.

这个段落的主题句是The replacement of humans by machines leads to the loss of value to human life.机器代替人类将会使人的生命失去价值。之后运用因果论证方式来详细展开，逻辑关系如下：

human tasks be performed by machines;

comparisons between human and machine;

a company will compare the two;

people are evaluated not for their worth as human beings,but for their effectiveness at performing a specific function;

the worth of a person’s life depends on their capacity;

person no reason to remain after serving their function;

genocide against the elderly and the disabled.

最后作者又论证了genocide产生的原因，也就是their burden on society would not be made up for by any production。从这个论证过程可以看出，作者论证了machines的使用会导致genocide的过程，中间缺少任何一个环节就不能推出最终的结果。

通过这个例子我们看到，在运用因果论证的时候，需要注意：

1、紧扣文章的论点，突出原因分析与议题、论点结合的紧密性;

2、因果论证层层推进，遵循A导致B，B导致C，C导致D的论证方式，中间不能出现逻辑断层，保证逻辑的严谨性和深入性。

因果论证的一些常见标志词有哪些呢?

文章中出现了如

because, warrant, lead to

等表示因果关系的词，除此之外，表达因果关系常用的词或短语还有：

consequently, thus, result from, originate from, since, thus, therefore, be responsible for等。

记住以上这些高频词，会让你的ACT写作论证时更出彩的。

2. 假设论证

假设论证是运用假设推理对论点进行分析的一种情况。

假设论证有两种形式：真实假设、非真实假设。

真实假设：

假设一个可能会发生的情况。如关于电子产品的好处与坏处，假设这个社会普及电子产品，或者人们过度使用电子产品，将会出现什么样的状况。

非真实假设：

假设一个不可能发生的情况。如关于电子产品的好处与坏处，我们假设不存在电子产品，将会出现什么样的生活，进而论证我们是需要电子产品的。而我们目前以及以后的生活中，不存在电子产品这种情况是不可能发生的，所以这就是非真实假设，从反面来论证论点的合理性。

同样拿上一段话为例：

Sentence 1: If a company executive wants to see…

Sentence 2: When this occurs, the people on the team…

Sentence 3: If a person is judged only on his or her capability…

在论证machines让人lose human value时，作者数次运用假设论证。

句1: 假设如果公司的管理者想要知道robotic system是不是能代替inventory team，将会导致comparison的发生。

句2: 当这种现象发生的时候，人们的价值不在于人性的价值，而在于完成一项工作的效率。

句3: 如果对一个人的判断取决于能力大小，那么发挥完功能就不再有作用。

假设论证的一些常见标志词有哪些呢?

如if, suppose, assume, provided that, in case…

3. 举例论证

举例论证是议论文中的一种方法。通过列举真实、可靠，有代表性的事例证明论点。通过列举典型事例，具体有力地证明了中心论点，增强了说服力。在ACT写作改革后，话题不再局限于教育类的题目，而是更广泛的社会类或者其他更加抽象的题目，所以可以利用举例论证的方式增强话题的真实性。举例论证的时候尽量避免俗例或没有代表性的例子，而是举一些如名人、有代表性的事例。

例证可以分为事例和语例两类。

事例：以当前的或者历史的事件或人物作例证。

语例：用专家、学者、知名人士等的话作例证。

旧版满分作文：

【例2】

As machines increasingly perform all our basic tasks, society is able to produce more. The additional production adds material value to our society and frees people up from these low-skill tasks. This is in agreement with Perspective Two which claims that this industrialization leads to more prosperity. For example, in the 18th century, short-staple cotton that was grown in the Southern United States required an immense amount of labor in order to seperate the seeds from the fiber to process the cotton to make it marketable. However, in the mid-19th century, Eli Whitney, an American entrepreneur, invented the cotton gin, which allowed for automation of cotton processing. This machine replaced the need of a large work force for the process and greatly improved production. As a result of the cotton gin, short-staple cotton production skyrocketed, increasing by more than 10 times in the South while bringing prosperity to the region and setting in motion a new industrial era in America.

这一段的观点是Society is able to produce more.作者在这里引用cotton gin的例子，来说明machine代替人类之后，明显的produce more。运用具体的历史事件来说明观点。

具体的事件包括哪些部分?我们来分析一下：

When-in the 18th century

What—short-staple cotton

Where—in the Southern United States

Why—required an immense amount of labor in order to…

Who—Eli Whitney

Function-replaced the need of a large work force

Result-increasing by more than 10 times and setting in motion…

具体的事例在列举的过程中包括了时间、地点、人物、事件以及作用与影响。

但是也有另外一些举例方式，如新版满分作文三个body段的三个例子：

【例3】

For example, in the automotive industry, most of a car’s individual components are manufactured by pre-programmed robots which have much greater and more precise output than would be possible for a human.

【例4】

For example, before the first airplane was invented, people could only dream of human flight, but at the moment of takeoff, a whole new world of unimaginable possibilities was suddenly within our grasp.

【例5】

Take the example of self checkout systems in grocery stores. Self checkout permits consumers to procure their goods and get out of the store quickly.

作者在三段运用了三个例子，分别是robots, airplane和self checkout，每个例子并没有给出具体的时间地点原因等，仅用一句话来概括例子的引用的事物。

在举例论证的时候，包括简单例证和复杂例证。

简单例证是用一两句话来概括事件，复杂例证是指完整的、详细的举例。大家在写作的过程中，要根据时间的多少、篇幅长短和论证的深入程度，善于结合利用简单例证和复杂例证。

今天小编就和大家分享以上内容，希望大家能够熟练掌握，对同学们2018年ACT考试会有所帮助的，小编会继续更新ACT考试难度，ACT培训机构以及ACT写作等相关内容。