Discuss writing a paper that has validity. Cover fact and fiction, supporting evidence, bias, and logic.
A paper that has validity must be credible, which means convincing and believable. The key to achieving this lies in backing up or illustrating your ideas with quotes and examples (supporting evidence). For example, if you want to prove in an English paper that a character in a novel is evil, you need to go back to the text and find quotes or examples that show this character's evil nature. Likewise, if you are asked to research and write about ways the food industry encourages obesity, you have to find specific examples of what the food industry does. It's not enough to say that food conglomerates stuff calories into junk food. Instead, you have to find examples of specific types of junk food and discuss how and why they are so caloric. In short, to write a valid paper, you must back up every statement you make with a quote or evidence that convinces your reader that what you say is true or at least convincing enough to be worth considering.
To produce a valid or persuasive paper, you also need to avoid biased sources and to be aware of your own possible biases. If you are biased, you might throw out evidence that contradicts what you already think you know and not offer a balanced argument. This is poor scholarship. A valid paper admits the strengths of its opponents and then argues against them. It does not include information that is not factual or that has been distorted in some way to make a point. For example, if you were quoting a source, you would not ellipse (leave out) words that were important to understanding what the author really meant. You would also use sources that any educated person would consider authoritative and unbiased, such as The New York Times or a peer-reviewed scholarly journal.
A good paper is logically coherent, meaning the evidence you have gathered actually supports the points you are trying to make. In a valid paper, you point out any logical inconsistencies (fallacies) in the arguments your sources make. For example, one of your sources might attack a person rather than an idea, which is called making an ad hominem argument. A classic example of this would be to say we should not build a strong highway system because Hitler did. Hitler was clearly a terrible person, but the German highway system was one of his few good ideas.
Finally, we come to fact and fiction. You clearly want your papers to contain fact, not fiction, but this speaks as well to another issue. A convincing paper contains both logos (facts and statistics) and pathos (true stories). Very few people will read a paper this is simply a pile of facts, such as a list of average temperatures over the past 60 years. Statistics alone don't make an argument. Every paper needs true stories that illustrate what their facts mean in people's lives. At the same time, you don't want your paper to be all story: this is like serving a meal of nothing but dessert. A reader will trust much more in your paper's validity only if it includes ample servings of the "protein and vitamins" that facts provide.
In short, a valid paper uses believable sources, uses many quotes and examples to back up its ideas, balances facts with true stories to illustrate its points, works to use unbiased sources and points out the logical fallacies it finds in arguments.