7.4: Conclusion: Using Supporting Material to Make Your Case
Erika Berlin
Beyond the Podium Insight:
Evidence-based, ethical reasoning strengthens everyday communication in classrooms, workplaces, communities, and online.
Every effective speech rests on the foundation of credible evidence, sound reasoning, and ethical integrity. In this chapter, you’ve learned not just how to find supporting material, but how to evaluate, integrate, and connect it to your claims through reasoning that is transparent and audience-centered. These skills extend far beyond the classroom. They shape how you engage with information, advocate for ideas, and influence others in your daily life. Whether you’re presenting in a boardroom, writing for a community forum, or engaging online, your credibility depends on your ability to back your ideas with thoughtful, ethical support.
As you step beyond the podium, remember that every argument you construct, spoken or written, is an act of civic participation. The way you select, verify, and explain your evidence determines whether your audience perceives you as trustworthy and informed or careless and uncritical. In a world flooded with misinformation and AI-generated content, your commitment to credible, reasoned communication is what distinguishes you as an ethical communicator.
In the next chapter, we’ll shift our focus from what you say to how you begin saying it. You’ll learn how to craft introductions that grab attention, establish credibility, and preview your central message—setting the stage for arguments that not only inform but inspire.
Key Takeaways
- Supporting material is the evidence that develops and strengthens a speech by clarifying content, building credibility, and adding vividness.
- Select support for accuracy, relevance, and credibility; verify with lateral reading and the SIFT method.
- Mix types of support to reach diverse listeners: facts and statistics, definitions, examples, narratives, expert and eyewitness testimony, and analogies.
- Make your argument explicit: state the claim, present the support, and show the reasoning; use causal, analogical, or sign reasoning as needed.
- Use numbers and visuals with context so the audience understands why they matter; prioritize quality over quantity.
- Guard against reasoning errors: avoid circular arguments, red herrings, false authority, leaps from correlation to causation, and probability stated as certainty.
- Establish credibility in delivery with clear oral citations (author, credentials when relevant, title, source, date) and audience-centered explanations.
- Treat AI as a brainstorming partner, not a source of truth; verify all AI outputs and watch for bias, oversimplification, and hallucinations.
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