People should try to avoid bias when using support material. A person cannot avoid bias, but when using sources to support his or her claim, it is important to not just look for sources that share the same bias as the individual giving the speech. Finding sources that portray both sides of an argument at face value helps to provide a more accurate representation of the topic at hand. If someone were to portray an argument with evidence that is strongly biased towards their own opinion, the audience could be easily led to believe that the opposing side is inherently wrong, even though it was just not represented correctly. In summary, bias is bad when using supporting material and should be avoided to eliminate the possibility of inaccurately representing an opinion about a certain topic.
I really like how you explained this! I like how you added concepts from what we read in the They Say, I Say book in English!
I agree, seeing the argument from both sides and being unbiased can help strengthen your argument. By successfully addressing all views of a topic correctly, you draw your audience in rather than push them away if they disagree with you.