7 Formal Informative and Persuasive Speaking

In 1962, John F. Kennedy stood before a crowd at Rice University and delivered one of the most memorable speeches of the 20th century. At the height of the Space Race, the United States was competing with the Soviet Union for technological and symbolic dominance in space. Kennedy’s goal that day was not only to inform the public about the nation’s plans to reach the moon, but also to persuade them that the effort was necessary, worthwhile, and urgent.

He began by laying out clear, factual information—what the space program aimed to do, the challenges involved, and the resources required. This portion of the speech functioned as an informative foundation, helping the audience understand the scope and complexity of the mission. But Kennedy did not stop at explanation. He moved quickly into persuasion, framing the moon landing as a test of national character and ambition. His famous line—“We choose to go to the moon…not because [it is] easy, but because [it is] hard”—transformed a technical objective into a shared national purpose.

What made the speech effective was how seamlessly it combined these two approaches. The informative elements built credibility and clarity, while the persuasive elements gave the facts meaning and emotional weight. Kennedy understood that facts alone rarely inspire action, just as passion without substance can feel empty.

This moment illustrates a central idea in public speaking: informative and persuasive speaking are often deeply connected. Whether explaining a new idea or advocating for change, effective speakers must not only help audiences understand, but also give them a reason to care.

This chapter focuses on these two closely connected forms of speaking: informative and persuasive. It explores how speakers use information to build understanding and how they use argument and appeal to shape attitudes, beliefs, and actions. By examining both approaches together, the chapter shows how effective communication often depends on balancing clarity with purpose, ensuring that ideas are not only understood but also meaningful and compelling to an audience.

Formal Speeches

Public speaking, at its core, is about helping others make sense of the world. Sometimes that means clarifying, laying out ideas so an audience walks away better informed about a topic, issue, or process they may not have fully understood before. Other times, it means advocating, making a case for why something should change, be reconsidered, or acted upon. These two purposes give us the two most foundational types of speeches: informative and persuasive.

While the distinction between them seems straightforward, one teaches, the other convinces, in practice, the line can often blur. A well-delivered informative speech can subtly shape how people think by framing information in a particular way, and a persuasive speech almost always depends on clear explanation to establish credibility and understanding before it can influence attitudes. The effectiveness of both often rests on how well the speaker organizes ideas and connects them to what the audience already knows or values.

The difference, ultimately, lies in intent. Informative speaking prioritizes understanding, aiming to increase knowledge without requiring agreement or action. Persuasive speaking prioritizes influence, seeking to move an audience toward a particular belief, decision, or behavior.

This chapter explores both approaches not as rigid categories, but as flexible and overlapping tools for communication. It also highlights how speakers often move between informing and persuading within the same message, depending on the needs of their audience and the goals of their speech.

Clarity Without Agenda: The Informative Speech

An informative speech is grounded in a simple but demanding goal: helping the audience understand something they did not previously know or fully grasp. This may involve introducing a completely new topic, clarifying a commonly misunderstood concept, or deepening knowledge about something familiar by adding context, detail, or structure.

What makes informative speaking challenging is not simply the content itself, but the discipline it requires in presenting that content. Speakers must carefully select and organize information so that it is both accurate and accessible, avoiding unnecessary complexity while still maintaining depth and precision. Equally important is the need to resist shaping the audience’s interpretation toward a preferred conclusion, even when the topic naturally invites opinions or debate.

Instead, effective informative speakers act as guides, helping the audience navigate information without directing where they should ultimately land. This involves using clear definitions, logical organization, and relevant examples to support understanding while remaining neutral in tone and intent. When done well, informative speaking empowers listeners to form their own interpretations based on a solid and well-structured foundation of knowledge.

Consider a historical documentary about the Apollo 11 Moon Landing. A strong documentary might explain the political context of the Space Race, the technological challenges involved in building and launching the spacecraft, and the experience of the astronauts during the mission. It may use narration, archival footage, and expert interviews to make the event understandable and engaging without directing the audience toward a specific judgment.

While viewers may come away feeling inspired or impressed, the documentary’s primary purpose is not to argue for increased space funding or to persuade viewers about policy decisions. Instead, its role is to present information in a way that allows audiences to form their own interpretations based on evidence and context. This distinction is what separates informative communication from persuasive communication in practice. No account or speech is ever entirely objective or delivered from a completely neutral stance, but it is the responsibility of a polished and ethical speaker to strive toward that ideal.

Types of Informative Speeches

Informative speeches can be organized around several broad categories, each offering a different angle for teaching an audience. These organizational patterns help speakers decide not only what to include, but also how to structure information in a way that makes it easier to understand and remember. Choosing the right approach depends on the topic itself as well as what the audience needs in order to follow the message clearly.

Table 7.1

These categories are not restrictive so much as they are starting points. A speech on a person, for instance, may also involve events, concepts, and issues. The key is deciding what the audience most needs in order to understand the topic.

Methods of Informing

If informative speaking is about teaching, then these four methods—defining, describing, explaining, and demonstrating—serve as its core instructional tools. Each one helps the audience understand information in a slightly different way, whether by clarifying meaning, creating vivid mental images, breaking down complex ideas, or showing how something works in practice. Most effective speeches rely on a combination of these methods, using them strategically to reinforce understanding and make the message more accessible and engaging.

Defining

Defining establishes what something means, often from multiple angles. A speaker might provide:

• A denotative (literal) definition
• A connotative (implied or cultural) meaning
• The term’s etymology or origin
• Comparisons to related ideas

For example, defining “democracy” might involve tracing its roots to the Greek demos (people) and kratia (power), while also distinguishing it from other forms of governance. A speaker might also discuss how some people may associate the word with “freedom,” while others may equate it with “participation.” The goal is not just to label the concept, but to situate it.

Describing

Describing focuses on characteristics (i.e., what something looks like, feels like, or how it presents itself). This can include physical details, psychological traits, or narrative elements. When describing a place like Tokyo, a speaker might move beyond population statistics to evoke the density, the rhythm of daily life, or the contrast between tradition and modernity. Description helps transform abstract knowledge into something more tangible.

Explaining

Explaining addresses how something works or why it matters. This method requires careful attention to audience knowledge. Overly technical language can obscure meaning, while oversimplification can lead to misunderstanding or condescension. A speaker explaining how vaccines function, for instance, might focus on the immune system’s response rather than the biochemical details of mRNA, depending on the audience. The aim is clarity, making complex processes intelligible without distortion.

Demonstrating

Demonstrating walks the audience through a process step by step. This is especially useful for speeches about how to perform a task or understand a sequence. Whether explaining how to prepare a recipe or how a piece of legislation becomes law, the speaker must organize steps logically and present them in a way the audience can follow. Demonstration turns understanding into potential action, even within an informative framework.

Structure and Delivery

Like all formal speeches, informative speeches rely on a clear and familiar structure: an introduction that captures attention and previews the topic, a body that develops main points in a logical order, and a conclusion that reinforces key ideas. This is not new material, but a refresher meant to show how these foundational elements apply specifically to informative speaking.

Even when persuasion is not the goal, structure still plays a crucial role. It helps audiences follow the flow of information, process complex ideas, and retain what they hear more effectively. In this sense, organization is what turns information into something meaningful and usable rather than fragmented or overwhelming.

However, what distinguishes an informative speech from more informal forms of speaking—such as a wedding toast or casual remark—is the level of formality and precision involved. Informative speeches often require clearer transitions, more deliberate organization, and the use of credible sources to support accuracy. The emphasis is on clarity, neutrality, and reliability rather than emotional spontaneity or personal storytelling alone.

Delivery also contributes to credibility. Confident posture, controlled gestures, and vocal clarity signal preparation and professionalism, reinforcing the message without distracting from it. These nonverbal elements work alongside structure and evidence to ensure that the information is not only delivered, but understood and trusted.

Influencing Thought and Action: The Persuasive Speech

If informative speaking asks, “What does the audience need to understand?”, persuasive speaking asks, “What do I want the audience to do with that understanding?”

Persuasive speeches are designed to influence beliefs, values, and attitudes, and in many cases, to motivate some form of action. Unlike informative speaking, which prioritizes neutrality and explanation, persuasion is explicitly directional—it advances a clear claim and supports it with structured reasoning, evidence, and appeals to audience needs and values.

Persuasion involves the strategic use of communication to shape how an audience thinks, feels, or behaves. Importantly, it is distinct from coercion or manipulation. Rather than forcing agreement or misleading an audience, ethical persuasion relies on transparency and trust. It draws its strength from three key elements:

• evidence and reasoning, which support logical consistency;
• credibility, which establishes the speaker’s trustworthiness;
• and emotional connection, which helps the audience see why the issue matters to them personally.

A historical example can be seen in the speeches of Bayard Rusting during the Civil Rights Movement. His arguments appealed to constitutional principles and justice, grounding his message in logic, while his moral authority as a leader strengthened his credibility. At the same time, his language evoked powerful emotional responses that made the stakes of inequality feel immediate and human. The result was not instant compliance, but a gradual and lasting shift in public awareness and attitudes.

The Rhetorical Triangle

Persuasive speaking is rooted in the classical tradition of rhetoric, most often associated with the ancient Greek philosopher Aristotle. One of his most enduring contributions to the study of communication and influence is the rhetorical triangle, a framework that explains how effective persuasion depends on the interaction of three key elements: logos, ethos, and pathos. Aristotle’s work laid the foundation for much of what we understand today about public speaking, argumentation, and influence, and his ideas remain central in modern communication studies.

• Logos refers to the logical structure of an argument and the use of evidence and reasoning.
• Ethos concerns the speaker’s credibility, character, and trustworthiness in the eyes of the audience.
• Pathos involves emotional appeal and the ability to connect with the audience’s feelings, values, and lived experiences. Together, these three elements shape how a message is received and interpreted.

The impact of this triangle extends beyond persuasion alone; it influences public speaking more broadly by shaping how speakers build trust, maintain attention, and create meaning. A speech that relies too heavily on logic may feel cold, while one driven only by emotion may lack credibility. Similarly, a strong reputation alone cannot sustain an argument without substance or connection.

For example, a political speech might present economic statistics to establish logos, highlight the speaker’s experience or leadership to build ethos, and include a personal story about a struggling family to evoke pathos. Each component reinforces the others, creating a more balanced and compelling message that resonates with audiences on multiple levels.

Theories of Influence

Persuasion is not only an art form but also a psychological process, and understanding how people actually change their attitudes can make a speaker significantly more effective. This is where theories of influence become important: they explain what is happening beneath the surface when an audience is being persuaded. Rather than relying on intuition alone, speakers can use these frameworks to design messages that are more targeted, ethical, and impactful.

One foundational concept is cognitive dissonance, first introduced by Leon Festinger. This theory describes the mental discomfort people experience when their beliefs and behaviors are inconsistent. Because humans are motivated to reduce this discomfort, they often adjust their attitudes, reinterpret information, or justify their actions to restore internal consistency. In public speaking, this becomes a powerful persuasive tool. A speaker might gently highlight a contradiction between what an audience believes and what they actually do, encouraging reflection and, ideally, a shift toward greater alignment with the speaker’s position.

Another key framework is the Elaboration Likelihood Model (ELM), developed by Richard Petty and John Cacioppo. This model explains that persuasion occurs through two main pathways: the central route, where audiences carefully evaluate arguments and evidence, and the peripheral route, where they are influenced by surface cues such as speaker credibility, tone, or emotional appeal. When audiences are highly motivated and attentive, they are more likely to process information centrally. When they are distracted or less invested, peripheral cues tend to have a greater impact.

For public speakers, these theories matter because they provide a roadmap for how audiences actually process messages. A strong persuasive speech does not rely on a single approach but strategically combines both routes—offering solid reasoning for engaged listeners while also using credibility and emotional resonance to reach those who are less actively processing. Understanding these mechanisms allows speakers to move beyond guesswork and communicate with greater precision and intention.

Inducing Change

Persuasive speaking can aim for different kinds of change, depending on the speaker’s goal and the audience’s readiness to respond.

Some speeches seek short-term shifts, such as encouraging the audience to reconsider an assumption, reflect on a new perspective, or become more open to an issue they had not previously engaged with. Others aim for long-term change, such as adopting a new belief, changing a habit, or committing to a sustained behavior over time.

This process is often gradual rather than immediate. Persuasion typically begins by introducing an idea in a clear and accessible way, then reinforcing it through repeated exposure, supporting evidence, and consistent framing. Over time, this repetition helps the audience move from awareness to acceptance, and in some cases, to action.

For example, many public health campaigns do not expect instant transformation. Instead, they focus on gradually shaping attitudes and normalizing healthier behaviors—such as wearing seatbelts, reducing smoking, or getting regular medical screenings. Through repeated messaging across different platforms and contexts, these campaigns work to shift what audiences perceive as normal, acceptable, or necessary.

Key Considerations for Persuasive Speakers

Effective persuasion requires careful planning that goes well beyond simply stating an opinion. Speakers need to be intentional about how each part of their message works together to support a clear and defensible position.

This begins with purpose: identifying the specific change being advocated, whether it involves a shift in belief, attitude, or behavior. It then extends to audience analysis, which considers what values, experiences, or assumptions might already support the message—and what might create resistance. Understanding this helps a speaker frame their argument in a way that is more likely to be received thoughtfully.

Strong persuasion also depends on evidence, which includes facts, examples, statistics, and expert testimony that strengthen the credibility of the argument. Finally, speakers should be clear about the action they want the audience to take, even if that action is as simple as reconsidering a viewpoint or as concrete as changing a behavior.

Persuasive topics often center on questions of policy (what should be done) or value (what is right or important). Because of this, they frequently involve complex or contested issues where audiences may already hold strong opinions. Effective speakers acknowledge this complexity rather than ignoring it, building arguments that are both thoughtful and responsive to differing perspectives.

Engaging Opposition in Good Faith

One of the defining features of persuasive speaking is the use of counterarguments, acknowledging and responding to opposing viewpoints rather than ignoring them. This feature is as much about building strong arguments as it is about better understanding opposing views. 

A well-developed counterargument typically begins by presenting the opposing view fairly and accurately, showing that the speaker understands alternative perspectives. It then acknowledges any valid points within that position, which helps establish credibility and fairness. From there, the speaker identifies limitations, gaps, or weaknesses in the opposing argument, often using evidence or reasoning to clarify why it may be less convincing or complete. Finally, the speaker reaffirms their own position, linking the response back to the central claim of the speech.

This approach strengthens persuasion in several important ways. It demonstrates intellectual honesty by showing the speaker is not avoiding disagreement, but engaging with it directly. It also helps anticipate and address audience concerns before they are fully formed, reducing resistance. Most importantly, it makes the overall argument more resilient, since a position that has been tested against alternatives often appears more credible, balanced, and thoughtfully constructed.

Some organizations, such as Braver Angels, encourage constructive dialogue between people with differing political views. They work to bridge the partisan divide by fostering conversations in which opposing perspectives are clarified and distilled, much like a skilled speaker refines ideas when preparing a persuasive speech. This makes them a valuable resource for strengthening this skill.

Informative and Persuasive Speaking in Relation

Although informative and persuasive speeches serve different primary purposes, they are not entirely separate categories in practice. Informative speaking often lays the groundwork for persuasion by ensuring that audiences understand key facts, concepts, or contexts before any attempt is made to influence their beliefs. Likewise, persuasive speaking frequently depends on clear explanation, since an audience cannot be moved toward a position they do not first understand.

The distinction between the two ultimately comes down to emphasis and intent. Informative speaking prioritizes understanding, focusing on clarity, accuracy, and neutrality so that audiences can form their own interpretations based on well-structured information. Persuasive speaking prioritizes change, whether that means shifting attitudes, reinforcing values, or motivating action through argument and appeal.

In real-world communication, these purposes often overlap. A public health presentation, for example, may begin by informing an audience about how a condition develops before persuading them to adopt preventative behaviors. Similarly, a policy speech may rely heavily on explanation to establish context before advancing a clear recommendation.

Recognizing when to inform and when to persuade—and how to integrate both effectively—allows speakers to adapt their message to different audiences, goals, and situations. This flexibility is a core skill in public speaking, as it ensures that communication is not only accurate and understandable, but also purposeful and responsive to context.

Quick Summary

This chapter examined the two foundational types of public speaking: informative and persuasive. While they have different primary goals, they are closely connected in practice. Informative speaking focuses on helping audiences understand a topic by presenting clear, accurate, and neutral information. Persuasive speaking builds on that understanding by aiming to influence beliefs, attitudes, or actions through evidence, reasoning, credibility, and emotional appeal.

The main difference lies in intent. Informative speeches prioritize understanding, while persuasive speeches prioritize change. However, in real-world communication, the two often overlap. Many persuasive messages rely on explanation to establish context, and many informative speeches can indirectly shape how audiences think about an issue.