After you have a sense of who your audience will be and how these readers might react to your thesis, you can begin to collect evidence to support your thesis. As you look for evidence, you need to evaluate the usefulness and relevance of each of your sources, and you need to be alert for possible bias.
As you read each potential source, consider the quality of the supporting evidence that the writer marshals to support his or her position. The more compelling the evidence, the more willing you should be to accept the writer’s ideas—and, perhaps, to integrate these ideas into your own essay.
To be convincing, the evidence that is presented in the sources you review should be accurate, relevant, representative, and sufficient:
Accurate evidence comes from reliable sources that are quoted carefully—and not misrepresented by being quoted out of context.
Relevant evidence applies specifically (not just tangentially) to the topic under discussion.
Representative evidence is drawn from a fair range of sources, not just those that support the writer’s position.
Sufficient evidence is enough facts, statistics, expert opinion, and so on to support the essay’s thesis.
(For more detailed information on evaluating sources, see Chapter 8.)
As you select sources, you should be alert for bias —a writer’s use of preconceived ideas (rather than factual evidence) as support for his or her arguments. A writer who demonstrates bias may not be trustworthy, and you should approach such a writer’s arguments with skepticism. To determine whether a writer is biased, follow these guidelines:
Consider what a writer explicitly tells you about his or her beliefs or opinions. For example, if a writer mentions that he or she is a lifelong member of the Sierra Club, a vegan, and the owner of a house heated by solar energy, then you should consider the possibility that he or she might downplay (or even disregard) valid arguments against a green campus rather than presenting a balanced view.
Look for slanted language. For example, a writer who mocks supporters of environmental issues as politically correct or uses pejorative terms such as hippies for environmentalists should not earn your trust.
Consider the supporting evidence the writer chooses. Does the writer present only examples that support his or her position and ignore valid opposing arguments? Does the writer quote only those experts who agree with his or her position—for example, only pro- (or only anti-) environmental writers? A writer who does this is presenting an unbalanced (and therefore biased) case.
Consider the writer’s tone. A writer whose tone is angry, bitter, or sarcastic should be suspect.
Consider any overtly offensive statements or characterizations that a writer makes. A writer who makes negative assumptions about college students (for example, characterizing them as selfish and self-involved and therefore dismissing their commitment to campus environmental projects) should be viewed with skepticism.