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David Merrill David Merrill

David Merrill

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David Merrill Education

  • M. David Merrill has nearly 40 years experience in the instructional design field, authored 12 books and numerous articles, technical reports, and book chapters. He joined the faculty at Utah State University in 1987 and continues to conduct his research there.

  • Earned his BA from Brigham Young University in 1961, his Ph.D from the University of Illinois in 1964.

    • Merrill, M. David and the ID2 Research Group. (1996). Instructional Transaction Theory: instructional design based on knowledge objects. Educational Technology, 36(3), 30-37.
    • Merrill, M. David (1997). Learning-oriented instructional development tools. Performance Improvement 36(3), 51-55.
    • Merrill, M. David (1997). Instructional strategies that teach. CBT Solutions, Nov./Dec. 1-11.
    • Merrill, M. David (1998). Knowledge objects. CBT Solutions, March/April, 1-11.


Merrill proposed a knowledge representation scheme consisting of knowledge components arranged into knowledge objectives.  He named this Component Design Theory (CDT).  CDT suggests almost all cognitive subject matter content (knowledge) can be represented as four types of knowledge objects:

  • Entities are things (objects)
  • Actions are procedures that can be performed by a learner on, to or with entities and their parts
  • Processes are events that occur often as a result of some action
  • Properties are qualitative or quantitative descriptors for entities, actions or processes


CDT defines knowledge via the components of a knowledge object.  A knowledge object and its components are a precise way to describe the content to be taught.  The components of a knowledge object are a defined set of containers for information.  The knowledge components of:

  • An entity name, describe or illustrate the entity
  • A part name, describe or illustrate the part of an entity
  • A property name, describe, identify a value, and identify a portrayal corresponding to this value for the property
  • An action name and describe the action and identify the process(es) triggered by the action
  • A process name and describe the process and identify the conditions (values of properties) and consequences (property values changed) of the execution of the process and any other process(es) triggered
  • A kind name, describe and define via a list of property values a class of entities, activities, or processes


Influential Theories

Instructional designers have long recognized the importance of analyzing subject matter for the purpose of facilitating learning via appropriate knowledge selection, organization, and sequence.  An early, widely used set of categories was proposed by Bloom and his associates circa 1956. Gagné proposed a taxonomy of learning objectives that found wide acceptance in the instructional design community.  For each of his categories Gagné proposed unique conditions for learning based on information processing theory.  Merrill elaborated and extended Gagné’s categories in his work on CDT.


Similar or Related Theories

Dijkstra and van Merrienboer propose an integrative framework for representing knowledge that identifies three types of problems:  categorization problems, interpretation problems, and design problems, as well as three levels of performance associated with the types of problems.  Each of these categories and levels corresponds to relationships among the components of knowledge objects.


Theory or Research? 

His work is both:  he initially conceptualized a theory, subsequently supported by research.



Merrill’s contribution to the instructional design field is as a thought leader, researcher, educator, consultant to major corporations and the government is major, as well as influencing a future generation of instructional designers and their learning.


Relevant Points

In Merrill’s reflection article, he discussed his most recent work to elaborate the content analysis required for task-centered instruction and how to define effective task-centered instructional strategy for teaching  complex content.  He sets forth “First Principles of Instruction”:

  • Task Centered – learning is promoted when learners are engaged in a task-centered approach
  • Activation Principle – learning is promoted when learners recall, describe or demonstrate relevant prior knowledge or experience
  • Demonstration – learning is promoted when learners observe a skills demonstration, receive guidance and observe relevant media
  • Application Principle – learning is promoted when learners engage in application with intrinsic or corrective feedback
  • Integration Principle – learning is promoted when learners integrate their new knowledge by reflection, discussion, and demonstration.


Personal Thoughts

In one of his many papers, Merrill recalls a conversation with B.F. Skinner.  I thought that was pretty cool.  Merrill is at his best when he explains things in every day language.  One quote I particularly liked is “there are really only two things that an instructor could do with content:  present it to the student or ask the student to remember or use the content.”  That sums up a complex theory in pretty simple language that anyone designing instruction can understand and apply.

 Video of Merrill

This overview was created by Dr. Karen E. Gardner. Download a printable version here: Merrill Overview

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