Knowledge is “stored facts”. All humans are capable of the storage of facts or information for retrieval at a later date.
There are at least 14 types of knowledge:
- A Posteriori Knowledge
- A Priori Knowledge
- Dispersed Knowledge
- Domain (Expert) Knowledge
- Empirical Knowledge
- Encoded Knowledge
- Explicit Knowledge
- Tacit Knowledge
- Imperative (Or Procedural) Knowledge
- Descriptive Knowledge
- Situated Knowledge
- Known Unknowns
- Unknown Unknowns
We store and retrieve knowledge in our minds through cognitive processes such as categorizing, memorizing, contextual recall and logical reasoning.
The 13 Types of Knowledge
1. A Posteriori Knowledge
A Posteriori knowledge is knowledge that we get directly from our own personal experiences.
A Posteriori is latin for ‘that which comes after’. So, when we talk about posteriori knowledge, we are talking about knowledge that comes after we have had some experiences. It is knowledge that is a result of our own experiences.
Some types of knowledge are not experiential. Theoretical, abstract and mathematical knowledge, for example, are derived from abstract or logical reasoning rather than direct observation.
- In Philosophy: Philosophers such as the existentialists and humanists tend to believe that posteriori knowledge is superior to theoretical knowledge. They reject the idea of a God or higher power because it cannot be observed in the real world. Others may disagree and argue that they have posteriori experiences of God every day of their lives when they see the beautiful world God created for them.
- In Education: Many social constructivist theorists believe that posteriori knowledge is excellent for learning because it helps students develop neural pathways. Learning by doing, experiencing and discovering is also popular in 21st Century educational approaches such as phenomenon based learning, problem posing education and play based learning.
2. A Priori Knowledge
A Priori knowledge is the opposite of posteriori knowledge. It is knowledge and facts that exist without the need to experience it. You can come to your conclusions through reason alone.
An example is: 1 + 1 = 2. You can figure this out without actually getting two separate things and placing them in front of your eyes to count them. You use your A Priori knowledge of mathematical principles to figure it out!
- In Philosophy: A Priori means ‘that which comes before’ in latin. It was a term commonly used by philosophers including Emanuel Kant in Critique of Pure Reason to come to philosophical conclusions. Many philosophers believe A Priori knowledge is a superior form of knowledge because it is objective and can be derived independently, without context or bias.
- In Science, Architecture and Engineering: Many great scientific, architectural and engineering feats have been achieved through A Priori knowledge. For example, the engineer is able to order a multi-million dollar bridge to be constructed and be confident that it will withhold the weight of trucks and cars because she has used her A Priori knowledge of physics to guarantee the bridge will hold its weight.
3. Dispersed or Distributed Knowledge
Dispersed knowledge is knowledge that no single person has the capacity to see in its entirety. The knowledge is dispersed or spread out among many different people. If we want to bring a whole lot of knowledge together to achieve something great, we need to get a team of experts on different topics together to input their knowledge to achieve our goals.
- In Surgery. Your surgeon may be the expert in fixing hearts, but he could not conduct the surgery without other specialists and anaesthesiologists who have knowledge and perspectives that the surgeon is not trained in.
- Running a Business. When a small business reaches a certain size, the business owner realizes they can’t possibly do all the tasks by themselves. They aren’t an expert in accounting, but the accounts need to be kept. They aren’t an expert in marketing, but there are marketing experts out there. So, they employ an accountant and a marketer. The business flourishes, despite no one person in the business having all the diverse skills and knowledge sets required to run the business on their own.
- Google Search. It is said that the google search algorithm which decides who will rank number 1 in a google search is not known and understood by one single person alone. So many people have contributed to it over time that different people know different features of how it works, but no one has all the knowledge about it in their brain alone.
4. Domain or Expert Knowledge
Domain knowledge is deep knowledge about a particular domain or discipline. We might also call it expert knowledge. A person with domain knowledge is incredibly knowledgeable within their discipline but may just have general knowledge about everything else.
- University Education. After compulsory education ends, many people continue studying at university. When we go to university, we get the opportunity to specialize in a specific domain: maybe it’s Computer Sciences, Communication Studies, or Teaching. This is even more the case at postgraduate level. Many such university degrees are all about developing specific domain knowledge rather than broad generalized knowledge (with the possible exception of liberal arts degrees).
- Industrial Revolution. Henry Ford revolutionized manufacturing by creating the factory line based on domain knowledge theory. Instead of getting five people to build five different cars, he got a bunch of different experts to work on each. One person was an expert on wheels, another on engines, and another on the body. By developing expertise, these people became very efficient at building their part of the car, and the cars were manufactured at a much faster rate.
5. Empirical Knowledge
Empirical knowledge is knowledge obtained through the senses. It is distinct from A Posteriori knowledge because empirical knowledge must be experienced through the senses alone. It cannot be a metaphysical, reflective, dream or other a posteriori experience.
Here is a quick summary of that distinction:
- Posteriori knowledge: knowledge derived from any experience.
- Empirical knowledge: knowledge derived from experience observable by the senses.
- Research. Most research (both qualitative and quantitative) is empirical. If you read a piece of research in a journal article, it will report on something that was observed, such as answers to interviews or research participants’ responses to an exam.
6. Encoded Knowledge
Encoded knowledge is knowledge that has been recorded in symbolic codes. This makes the knowledge easily retrievable by people who know how to (or have tools that help them) decode that knowledge at a later date. We might also call it ‘stored’ knowledge.
- Written Language. Written English is the code of our language. We encode knowledge when we write it down and anyone who can read our ‘code’ (i.e. anyone who can read in English) can then decode it at a later date.
- Road Signs. We have also created generalizable codes in our road signs. Red octagon means ‘stop’, green light means ‘go’, etc.
- The Rosetta Stone. In 1799, archaeologists discovered the Rosetta Stone. It is a stone that dates back to 196BC and contains inscriptions written in Egyptian hieroglyphics, ancient Greek and Egyption demotic scripts. Because all three inscriptions were of the same information in different languages, the stone helped scientists to decipher Egyptian hieroglyphics. This unlocked access to all other Egyptian texts written in hieroglyphics and allowed us to decode the encoded knowledge of the Egyptians.
- Digital Data. Knowledge can be encoded into binary data that is stored on digital devices such as cloud computers and USB drives. In order to decode the knowledge, computer software is required to turn those binary 1s and 0s back into a code we can understand, such as written words, spoken words, or images.
7. Tacit Knowledge
Tacit knowledge is knowledge that you have but cannot express. A person with tacit knowledge has usually had that knowledge for so long that they cannot remember how they learned it or why it is true. They are simply aware that it is useful, accurate knowledge that exists in their mind.
- Practitioner Knowledge. Many expert practitioners know how to do things out of intuition. An expert vet knows how to connect with a horse and settle its nerves but may be unable to explain how they can develop that relationship so quickly. An expert teacher may be able to diffuse a troublesome situation in a classroom but not really be able to explain to their apprentice teacher just how they did it.
- Digital Natives. Digital natives are children who have grown up around computers their whole lives. They will get a new piece of software and almost intuitively know how to manipulate it and find hidden features (much faster than their parents could!). When asked, the digital native may not be able to tell you why they knew a feature was under a certain drop-down menu: for them, it just seemed obvious to look there!
- Emotional Intelligence. People who have high emotional intelligence know how to communicate with people to make them feel welcomed and comforted. They know how to network and make friends quickly. However, they may struggle to explain quite how they do it to their friends.
8. Explicit Knowledge
Explicit knowledge is the opposite of tacit knowledge. It is knowledge that can be easily explained to outsiders. It is knowledge that we could quickly codify into words and express to others.
- User Guides and Manuals. A user guide will walk someone through how to use a product in a step-by-step explicit way.
- Recipes. Similarly, a recipe may spell out how to do things one after the other.
- Guided Teaching Practice. This is a teaching strategy that involves guiding students through a process in a methodological way. Once the student has been explicitly modelled the knowledge, the teacher steps back and lets the student practice applying their new knowledge without support.
Metaknowledge is knowledge about knowledge. Anything we know about knowledge (such as how it works, how to classify it, how we lose it, how to gain it) is considered metaknowledge. Everything on this article is metaknowledge: it’s information about knowledge!
- Taxonomies. A taxonomy is a model for classifying things. A famous taxonomy of knowledge is Bloom’s Taxonomy, which outlines different depths and levels of knowledge that people have. Another type of knowledge taxonomy is Biggs’s SOLO taxonomy.
10. Imperative (or Procedural) Knowledge
Imperative knowledge is ‘knowing how’. It is knowledge about how to carry out tasks effectively. This may involve specific steps or a general understanding of the process by which something gets achieved. Some people hold the secrets to their imperative knowledge close to their chest, such as when a grandmother passes down a family recipe to her granddaughter.
- Standard Operating Procedures in Business. Most large companies of project managers who set out standard operating procedures. These are the procedures that people must follow in order to achieve the goals of the business.
- Secret Recipes. The famous KFC 11 herbs and spices are said to generate their specific ‘KFC flavor’ from the procedures in which they are cooked. This procedural knowledge is highly classified and the intellectual property of KFC.
11. Descriptive Knowledge
Also known as propositional knowledge, descriptive knowledge is ‘knowing that’ something is true (as opposed to ‘knowing how’ something should be done). Descriptive knowledge can be learned through memorization and does not require significant practical experience in the field. By contrast, imperative (‘knowing how’) knowledge usually requires practical skill in a task.
- In Education. 20th Century teaching pedagogies like behaviorism focused exclusively on descriptive knowledge. Students learned facts through passive learning, without being given the opportunity to apply them to the real world.
12. Situated Knowledge
Situated knowledge is knowledge that emerges out of a specific context, community or culture. It is knowledge that is specific to that situation and is hard to understand from outside of that perspective. All of us have situated cultural knowledge. This is the knowledge that we’ve inherited from our cultures. Others might have different knowledge that has grown from different cultures and you may find it hard to understand their knowledge from your ‘outsider’ perspective.
- Cultural anthropology. Anthropologists and sociologists often need to situate themselves within a culture in order to understand the cultural perspectives and understandings that they are observing. As outsiders, they may find the situated knowledge, ritural and activities a little strange.
- Education. Situated learning theory by Lave and Wegner advocates that students should learn within the context in which the knowledge is applied. For example, someone should take up an apprentice as a baker’s aide in order to learn to bake bread, rather than learn it from paper.
13. Known Unknowns
When we have ‘known unknowns’, we are aware that there’s something that we don’t know or understand. Known unknowns are usually within our grasp of understanding because we are aware of what we need to learn and can seek out answers. This is in contrast to unknown unknowns, which are not even within our own horizon of awareness and therefore we cannot seek out answers.
- Confusion. When new information is presented to us but it causes confusion, we are aware that we don’t know enough about it. This may lead us to conduct research in order to find the answers.
- Curiosity. When we come across something new, it may cause us to become curious. We will then go about researching it because we are aware we don’t know much about it.
14. Unknown Unknowns.
Unknown unknowns are pieces of knowledge that we do not have and equally are unaware that we don’t have it. This is information that may be beyond our comprehension and indeed beyond our wildest dreams. It has never even entered our minds that unknown unknowns are a possibility.
- Theoretical Physics. Many theoretical physicists are very open about the concept of unknown unknowns. 200 years ago, the idea of a concept called ‘grey matter’ or ‘string theory’ was simply unknown and unknowable. Scientific knowledge was not advanced enough for it to even be on their radar. Science educators like Neil Degrasse Tyson and Bryan Cox often refer to unknown unknowns as the reason scientific research is so exciting.
- Religion. Many religious people may defer to unknown unknowns as things that are in the realm of God, not men. Things we do not know that we do not know are things that are in God’s hands.
There are many different types of knowledge. The knowledge forms outlined in this article are 14 major ways we can conceptualize knowledge and how it works.
Dr. Chris Drew is the founder of the Helpful Professor. He holds a PhD in education and has published over 20 articles in scholarly journals. He is the former editor of the Journal of Learning Development in Higher Education.