In paragraphs 1 and 2 of "What is an American?", the author supports his argument in two ways:
* **He cites historical evidence.** He points out that the United States was founded on the principles of liberty and equality, and that these principles have been embraced by people from all over the world.
* **He uses logical reasoning.** He argues that if America is a nation of immigrants, then it follows that there is no one definition of what it means to be an American. Instead, American identity is a matter of personal choice and individual beliefs.
Here are the specific passages from the text that support these two points:
* **Historical evidence:**
> "What is an American? That is a question that has been asked for centuries. There is no one answer that will satisfy everyone, but I believe that there are two key qualities that define an American. First, Americans are people who believe in liberty and equality. These principles were enshrined in the Declaration of Independence, and they have been central to American identity ever since. Second, Americans are people who come from all over the world. The United States is a nation of immigrants, and our diversity is one of our greatest strengths."
* **Logical reasoning:**
> "Since America is a nation of immigrants, it follows that there is no one definition of what it means to be an American. Instead, American identity is a matter of personal choice and individual beliefs. What unites us as Americans is not our shared ancestry or our common culture, but our shared commitment to the principles of liberty and equality."
In conclusion, the author supports his argument in paragraphs 1 and 2 of "What is an American?" by citing historical evidence and using logical reasoning. He argues that American identity is a matter of personal choice and individual beliefs, and that the United States is a nation of immigrants who are united by their shared commitment to the principles of liberty and equality.