Types of Evidence

When you support your thesis, you are revealing evidence. Evidence includes anything that can help support your stance. The following are the kinds of evidence you will encounter as you conduct your research:

Facts. Facts are the best kind of evidence to use because they often cannot be disputed. They can support your stance by providing background information on or a solid foundation for your point of view. However, some facts may still need explanation. For example, the sentence “The most populated state in the United States is California” is a pure fact, but it may require some explanation to make it relevant to your specific argument.

Judgments. Judgments are conclusions drawn from the given facts. Judgments are more credible than opinions because they are founded upon careful reasoning and examination of a topic.

Testimony. Testimony consists of direct quotations from either an eyewitness or an expert witness. An eyewitness is someone who has direct experience with a subject; he adds authenticity to an argument based on facts. An expert witness is a person who has extensive experience with a topic. This person studies the facts and provides commentary based on either facts or judgments, or both. An expert witness adds authority and credibility to an argument.

Personal observation. Personal observation is similar to testimony, but personal observation consists of your testimony. It reflects what you know to be true because you have experiences and have formed either opinions or judgments about them. For instance, if you are one of five children and your thesis states that being part of a large family is beneficial to a child’s social development, you could use your own experience to support your thesis.