Common Knowledge: Feast On What Everyone Knows

Common knowledge is that which everyone or nearly everyone knows. Usually it infers the community in which the knowledge is referenced. Since individuals hold different knowledge bases, common knowledge differs for everybody. The sky is blue. Fire is hot. Common knowledge reminds us of what others know without proof or explanation, thus making smooth communication and cooperation easier. Though it depends on the involved group, time period, and location.

The number one element of common knowledge is wide acceptance. Most people within a given group or context must know the information for it to be considered common knowledge. In fact, it should be so common that not only everyone knows it, but they know others around them know it. In mathematics, this would be the answer to “2+2”; in traffic, this would be the meaning of green and red lights; in tech circles, this would infer what “CTRL + C” or “CTRL + Z” means. Widely recognized, accepted, and understood stuff. Common knowledge.

Common knowledge plays a vital role in the collaboration of society. It reduces the need for foundational concepts to be explained, enabling efficient interaction. Like, when discussing climate change, it’s presumed that everybody knows carbon dioxide traps heat. Moreover, it serves to enforce unwritten social rules and expectations. Standing in line at a store without cutting need not be explained. When there’s a shared understanding, coordination is enhanced, and actions tend to align. In sports, for instance, teammates and opponents assume everybody knows the basic rules of the game. The upsides of common knowledge: efficiency, since there is no need to explain basic concepts; cohesion, as groups have a shared understanding; predictability, because reliable expectations are set; and adaptability, since context-specific actions and decisions become nearly automatized.

There’s where we run into challenges. What is common knowledge to one may be entirely unknown to another. Gestures like a thumbs-up are positive in some cultures and negative in others. Generational gaps also split younger and older audiences. And these false assumptions of “common” knowledge results in miscommunication and similar errors. Older folk think they are easily understood by the youngsters. Tech-savvy people think their non-specialist audiences get their tech-y jargon. What was “common” some years ago—such as operating a manual typewriter—is now niche. The disadvantages are clear: misjudging what others know leads to confusion, overemphasis on shared knowledge results in exclusion, and over-reliance on common knowledge stifles innovation.

Real life implications of common knowledge:

• Education: as a teacher, mentor, or coach, you can leverage common knowledge in your group to help your students or clients take in advanced topics more easily, such as mastery of fundamental mathematics before moving on to advanced algebra;

• Team: groups rely on the shared norms and expectations to function efficiently, so you, the leader, can clarify the deadlines and tasks more prominently to ensure everybody is aligned;

• Marketing: when advertising or launching a new campaign, use widely recognized symbols to tap into customers’ shared experiences and beliefs, such as a red heart emoji to symbolize love; vague advertisements never perform;

• Storytelling: writers, storytellers, and filmmakers often rely on common knowledge to give their characters and plots depth without overwhelming the consumer, such as by using analogies or relatable, widely understood concepts to describe lesser-known ones;

• Conflict: to mediate a conflict, shared values can be identified and used as a basis to find a compromise, such as determining what the end goal of both sides is and working towards a mutually satisfying outcome.

How to use common knowledge as a mental model: (1) identify the audience, understanding what the group’s background is to gauge what they already know; (2) clarify vagueness whenever you are in doubt of being understood to avoid miscommunication; (3) use shared knowledge as a starting point and build on top of it, introducing more complex ideas in order; (4) stay informed about changes and gaps of knowledge over time, and try to fill them in as fast as possible; (5) ensure that everybody is fairly treated and that you foster a culture of inclusivity.

Thought-provoking insights. “Knowledge is power, but shared knowledge is progress.” and “What we know is only as useful as what we think others know.” both highlight the core message: we shouldn’t overly rely on assumptions about what others know. Common knowledge is a very useful lens whenever you need to communicate something. Try to tap into what is already known and associate it with what is not. Otherwise, the gap in understanding between you and your audience might make your message too ambiguous, and therefore incomprehensible. As a general rule, assume they don’t know, and explain with what they definitely know.

Questions to reflect on:

1. What assumptions do I make based on what I believe is common knowledge?

2. What role does common knowledge play in my decision-making process?

3. How can I become a more effective communicator by understanding the knowledge of my audience?

4. What mistakes have I made by assuming others share knowledge they did not?

5. What strategies can I use to keep my common knowledge up to date?

Quotes that ache the strongest brains:

1. "Common knowledge is not so common." - Voltaire, French writer, historian, and philosopher.

2. "The only true wisdom is knowing you know nothing." - Socrates, Greek philosopher.

3. "What we know is a drop, what we don't know is an ocean." - Isaac Newton, mathematician and physicist.

4. "Knowledge has to be improved, challenged, and increased constantly, or it vanishes." - Peter Drucker, management consultant and author.

Example use cases:

1. Education: teachers use common knowledge to develop lessons and curricula that connect new concepts to students' existing understanding, ensuring an effective and relatable learning experience.

2. Team: collaborative teams rely on common knowledge, ensuring that all members are on the same page. Clarity makes teams work together effectively more than anything else.

3. Public policy: policymakers use common knowledge to design and implement policies that address broader societal issues and needs, ensuring their decisions are grounded in widely accepted information.

4. Social: individuals use common knowledge to navigate social situations, making assumptions about each others' beliefs, values, and behaviors to communicate more effectively.