A well-crafted written argument can change the world. Consider the Declaration of Independence or Martin Luther’s 95 Theses. Both written arguments reshaped how people thought about independence and faith, respectively, and each has had a lasting historical impact on our world. Similarly, both the Declaration of Independence and Luther’s Theses employ ancient rhetorical techniques in their writing. These modes of argument were thoroughly defined and described in Aristotle's "On Rhetoric," but have received many revampings over the years.

Logos

Logos refers to logic or reason in an argument. Developing your writing’s logos means attending dutifully to the logical progression of a train of thought. In order to do this, you must be up front about how you are defining certain key terms, as well as what facts about the world you are assuming in making your argument. Then generate reasonable and verifiable premises for your argument, and ensure that whatever conclusions you reach in your argument are justified by your premises. For example, in the Declaration of Independence, the document opens by defining the following self-evident truths about humanity: All people are created equal and have certain unalienable rights including life, liberty and the pursuit of happiness. The document then goes on to make a powerful argument for the United States' independence from England because the latter violated these self-evident truths.

Pathos

Pathos refers to the passion or emotion of an argument. Lunsford, et al., suggest that though pathos-driven arguments sometimes can be dismissed for being based too much in an emotional appeal, an appropriate sprinkling of emotion throughout your argument can go a long way toward convincing your readers. Specifically, you should develop examples that are emotionally laden. In this way, your writing’s pathos plays a supportive role to the argument’s logic, rather than a central role. For example, you might choose to build an example that focuses on baby kittens, rather than on adult sea lions, as more people are likely to feel emotionally attached to kittens than to sea lions.

Ethos

Ethos is your argument’s credibility. You can build your writing’s ethos by using expert testimony to support your position. For example, you might cite government websites or studies or well-known professors or scientists in the field about which you are arguing. By citing these sources, you are indicating to the reader that not only have you done your research, you also have found a lot of experts who support your argument. Aristotle maintained that uniting your positions with others made it more difficult to dismiss your written position as isolated and individual.

Kairos

Kairos is the timeliness of your argument. Aristotle suggested, and Lunsford, et. al. concur, that sometimes we don’t have control of external events that might impact our positions, though we do have control over when it is best to argue for certain things in writing. For example, following a tragic gun massacre, it would be unwise to craft a written argument about how gun laws should be eliminated. Similarly, following a spending scandal in a welfare program, it would be unwise to write something arguing for the expansion of welfare programs. Choosing the right time to make an argument often can be the difference between winning and losing.