Gagne's Conditions of Learning Lecture
This chapter will outline Gagne's Conditions of Learning, how this theory applies to education, its strengths and limitations and how it can be linked to practice within the educative system. It will begin with a definition of the key terms, moving on to consider its application in the educative world.
Learning Objectives of this Chapter
By the end of this chapter, we would like you:
- To understand the notion of Gagne's Conditions of Learning
- To understand how this idea applies to education
- To understand its strengths and limitations
- To understand how the notion can be linked to practices in the classroom
Robert Gagne puts forward the notion of conditions of learning, as opposed to a theory about learning per se (Quinn, 2000). He defines learning as an alteration in an individual's capabilities or disposition which continues over a period of time that cannot be put down to the natural process of maturation (Gagne, 1985). In addition, he regards learning as the means through which individuals and groups of people acquire the skills that are necessary for them to be accepted members of society. Furthermore, Gagne believes that learning is a direct result of different human capabilities (behaviours) which are required as a result of stimulation from both the environment and the thinking processes which happen within individual learners. Quinn (2000) comments that in this model, growth is regarded as being governed by genetics, whereas learning is shaped by the environment and how an individual interacts with it.
The foundations of Gagne's work lie in the concept of Behaviourism, based on the notion that through analysing observed behaviours, the necessary components to acquire a specific skill could be identified. From his observations of individuals' learning, he concluded that the process of learning a specific skill was dependent upon previous learning which led to his assertion that instruction should comprise of logical, sequenced steps which build upon prior learning. It is through this sequence of 'building knowledge' and the mastery of each component that learning can occur. Gagne put forward the idea that there are a number of different kinds of learned outcome which are dependent upon different conditions (both internal and external) that support these diverse types. He places these different learning outcomes into five performance categories which represent specific types of learning capability - verbal information, intellectual skills, cognitive strategies, attitudes and motor skills.
Quinn (2000) states that different learning capabilities includes what Gagne calls 'prototypes of learning', which might be regarded by some as the most basic form of learning by association. These broadly fall under Behaviourist principles and include classical conditioning, operant conditioning, verbal association learning and chaining. Quinn (2000) observe that these elements are seen as basic in that they only make up parts of specific capabilities and cannot be regarded as an explanation of complex learning skills, although it must be acknowledged that association learning is an integral (if basic) part of all types of learning.
What is Gagne's definition of learning? Try to explain this in your own words. How closely does this align with the way you've previously thought about what 'learning' means? What concept/s do you think Gagne regards as integral to all types of learning and why?
Driscoll (2000) observes that the work conducted by Gagne extended that of Benjamin Bloom, who put forward the idea that individuals learn across three separate domains - cognitive, affective and psychomotor. Bloom's taxonomy (classification) deals with the cognitive domain and was originally developed for use in universities, although it was quickly discovered by workers across the field of education including classroom teachers, researchers, administrators and curriculum planners (Anderson & Sosniak, 1994 cited in Moore and Stanley, 2010, p. 3). Moore and Stanley (2010) observe that it has become the leading model when considering critical thinking skills. This classification system sees each tier build upon the previous one, with progress only being made in terms of cognitive skills once there has been a mastery of the lower levels. Bloom considered that there were six levels - knowledge, comprehension, application, analysis, synthesis, and evaluation. Each of these levels describes a particular means of thinking, although it is important to point out that each classification carries equally complex skills, making the lower end of the tier just as challenging as any of the others (Moore and Stanley, 2010).
Knowledge is thought to be the lowest tier and it is the one with which practitioners in the classroom are most familiar. Descriptions of this involve recalling previously learned material such as facts, basic concepts, terms and answers (Barton, 1997 cited in Moore and Stanley, 2010, p. 3). Demonstrations of this skill include being able to recall lists or answer basic questions such as the flags of the world, capital cities of the world or times tables in maths. Simply identifying a character in a book demonstrates the skill of knowledge. Moore and Stanley (2010) note that Bloom provided words which represented this level such as who, what, when, where, which, why, choose, how, show, list, select, name and tell.
Comprehension is demonstrated through understanding concepts through comparing, organising, interpreting, translating, describing and recounting the main ideas (Barton, 1997 cited in Moore and Stanley, 2010, p. 3). When practitioners ask students to explain how they have come to an answer or how they worked out a problem or when practitioners ask children to recount in their own words what has just been taught, they are demonstrating this skill; it confirms to the practitioners that they have understood what they have been taught. It can also be demonstrated by recounting facts within a piece of work such as a report on a book which gives information without opinion. Words which are associated with this tier are compare, contrast, interpret, explain, demonstrate, illustrate, outline, relate, summarise and classify (Moore and Stanley, 2010).
Application sees learners being able to solve problems in different circumstances by applying the knowledge, facts, rules and techniques that they have acquired (Barton, 1997 cited in Moore and Stanley, 2010, p. 4). This requires learners to utilise specific strategy to solve problems in different circumstances, and apply fact and/or theory to a new idea. Moore and Stanley (2010) state that this is what students do when they read a map and use the scale - they have been taught how to use the scale but have not been taught the distance between two points and will need to apply this skill of reading the scale to find out the answer. Key words and phrases in this level are build, choose, construct, develop, apply, organise, experiment with, select, identify, plan, solve and model (Moore and Stanley, 2010).
Analysis involves students breaking information down into its constituent parts in order to discover causes and find evidence to support inferences and generalisations (Barton, 1997 cited in Moore and Stanley, 2010, p. 4). Students utilise this skill when they are asked to compare the main characters in different stories to discover the similarities and differences between them. Common words utilised in this tier are analyse, classify, compare, contrast, discover, examine, simplify, distinguish, motive, inference, and conclusion (Moore and Stanley, 2010).
Synthesis is a skill which requires learners to compile information together in different ways, in alternative patterns and/or solutions (Barton, 1997 cited in Moore and Stanley, 2010, p. 4). Moore and Stanley (2010) state that learners demonstrate this when they write a different ending to a story, offer innovative solutions to a specific issue such as global warming, which allows them to be creative in their thinking processes and their use of information. Keywords in this tier include build, combine, compile, construct, create, design, develop, formulate, invent, originate, propose, discuss, improve, adapt, theorise, elaborate, test, and improve (Moore and Stanley, 2010).
Evaluation is the tier which requires learners to assess the validity of information or ideas to present and defend an opinion (Barton, 1997 cited in Moore and Stanley, 2010, p. 5). This can range from children justifying why they have a favourite colour or have chosen a book or providing a justification for why they have taken one side or another during the course of a political debate. Within education, practitioners tend to use this skill more frequently than the previous two as they, personally, are more familiar with it. Some of the words central to this tier are criticise, judge, compare, opinion, support, prove, justify, appraise, interpret, disprove, defend, evaluate, measure, select, prioritise, explain and assess (Moore and Stanley, 2010).
In addition to this, Bloom developed the notion that there was a taxonomy of levels within the affective domain (Krathwohl, Bloom and Masia, 1964 cited in Driscoll, 2000, p. 348). A similar taxonomy for psychomotor outcomes was put forward by Simpson (1966/67, cited in Driscoll, 2000, p. 348). It was Gagne who proposed a taxonomy of learning outcomes which integrated all three domains, leading to the five categories:
Verbal information learning involves the type of knowledge which allows individuals to relate, tell or verbalise information using sentences or propositions which is sometimes called declarative knowledge (Quinn, 2000). Verbal learning takes three forms - names or labels, facts or single propositions and organised verbal knowledge.
- Names or labels:
Names and labels tend to be learnt as concepts or skills as required which dictates that only one or two can be learnt at a specific time. Clearly, there are occasions when it is necessary to attempt to learn several different names at one point in time, for example when a teacher meets a new class or a child joins a new class, making the situation stressful and difficult.
- Facts or single propositions:
The common consensus is that facts are logged or stored in the memory as meaningful statements or propositions, as opposed to being odd words or phrases, in some form of logical network.
- Organised verbal knowledge:
Organised verbal knowledge involves collecting a series of propositions into some form of connected speech which can be referred to as prose. Evidence would suggest that the prior knowledge that individuals have impacts upon the learning of new information from prose texts as a result of their experiences which have formed specific 'global schemata' governing particular events or situations.
Driscoll (2000) states that Gagne's ideas surrounding verbal information appear to involve the first two levels of Bloom's taxonomy (knowledge and comprehension) as a result of the fact that individuals can learn things by rote (without any consideration of meaning) and, at a later date, can recall and paraphrase/explain the information that they have learnt.
Intellectual skills form a hierarchy of subcategories which require individuals to learn and understand the previous phase in the hierarchy in order for learning to occur (Quinn, 2000). These skills can be regarded as knowledge about how to perform certain tasks (procedural knowledge) and are characterised by rule governed behaviour. These rules qualify the relationships between different components or concepts which rely upon an individual's ability to tell the difference between the various inherent characteristics of things (Quinn, 2000). The subcategories are discrimination, concrete concepts, defined concepts, rules and higher-order rules which Gagne (1985 cited in Driscoll, 2000, p. 351) refers to as 'a set of component skills that must be learned before the complex skill of which they are a part can be learned.'
Discrimination refers to learners being able to make distinctions between different inputs and responding differently according to each one within a particular class or group. For example, being able to distinguish similar birds as a result of their markings or being able to tell the difference between gauges on an instrument panel. Concrete concepts involve responding in a uniform way to all members of a particular class of observed events; this involves being able to identify similarities among objects, events or people, thus requiring a specific, single response. Gagne and Driscoll (1988, p. 50) state that this is demonstrated by "the ability to identify a class of objects, object qualities, or relations by pointing out one or more instances of the class." For example, classifications within music (jazz, classical) or stating that the moon, a penny and a manhole are examples of objects that are round. Defined concepts provide definitions for objects, qualities of objects or the relations between objects so that individuals are able to identify them (Tuckman and Monetti, 2011). Tuckman and Monetti (2011) point out that learners can demonstrate this by identifying instances of particular concepts, for example, having knowledge of what a chemical element is will enable learners to identify elements from within a list of chemical substances. The difference between concrete and defined concepts is that individuals must have a firm grasp of what a defined concept means or its essential features to be able to recognise it. Rules provide learners with the ability to do something as opposed to simply describe how something is done, linking actions to conditions (Tuckman and Monetti, 2011). An example would be a young reader's use of phonetics to decode printed symbols which, in turn, allows them to pronounce letter and word sounds, and to find out their meaning.
Gagne and Driscoll (1988) state that rules enable connections to be made between instructions and/or objects and a specific type of performance - once you have learnt the rules for, for example, solving equations, learners are able to find a solution for any equation which fits those specific rules. Higher-order rules are simple rules combined together to make a more complex rule (Gagne, cited in Tuckman and Monetti, 2011, p. 491). An example of this is provided by Tuckman and Monetti (2011), who state that when practitioners plan lessons they employ higher-order rules which allow them to select which topics need to be covered, how to decide upon their objectives, how to present the lesson material, and how to evaluate whether the students have grasped the lesson objective.
Cognitive strategies refer to the way in which things are learnt (Tuckman and Monetti, 2011) including the way in which learners manipulate their own learning, thinking, feeling and actions (Driscoll, 2000). As far as Gagne (1985) was concerned this involved learners arriving at strategies through trial and error or by being taught these skills by others. One way in which this can be shown is through the demonstration of creative thinking to find innovative solutions to different problems. These strategies are sometimes referred to as executive control processes (Tuckman and Monetti, 2011) which allow learners to manage the learning process for themselves.
The previous three categories could be seen to fall under the cognitive domain whereas attitudes can be considered as the affective domain (Driscoll, 2000). Gagne (1985) described attitudes as being internal feelings which impact upon personal action in specific circumstances, for example, attitudes towards pollution and ecology will have an impact upon the way in which individuals react towards recycling their domestic rubbish. These attitudes, once organised into a consistent set or category, become a philosophy or worldview which many term as values (Driscoll, 2000). Tuckman and Monetti (2011) observe that an individual's values or attitudes about themselves dictate their levels of self-esteem, influence their behaviour and performance, and consequently their motivation.
This category corresponds to the psychomotor domain. This covers the "precise, smooth and accurately timed execution of performances involving the use of muscles" (Gagne and Driscoll, 1988, p. 59). Examples of motor skills include the performance of sports activities (dribbling a basketball, serving a tennis ball, kicking a football, passing a rugby ball) or specific types of working activities such as driving a car. Some of these skills can be more complex than others for example, coordinating the movements when tacking in a boat or performing a complex set of steps as a part of a dance. Clearly, motor skills such as these require some form of cognitive output and work in conjunction with these skills (Driscoll, 2000).
It is important to remember that this taxonomy is predicated by the assumption that different outcomes require different learning conditions, and the careful design of instructional activities which allow learning goals and outcomes to be met (Driscoll, 2000).
What are Gagne's five performance categories? Again, try to summarise each one in your own words. How, in your opinion, do they overlap as individuals learn? You could perhaps try to draw a diagram to illustrate this if you find it helpful.
According to Gagne, Briggs and Wager (1992), it is important to group learning goals according to their intended outcomes. This involves deciding, during the course of planning, what is meant to be learnt and what the learner should be able to do at the end of a specific session. The setting of learning goals has become a standard part of the teaching process, in the respect that they are useful to practitioners in terms of informing their planning and being able to evaluate the success, or otherwise of a session or set of sessions. It is imperative that there is a link between these instructional goals, the content of the lesson and assessment measures in order to assess student progress. The only way to ensure those links is to provide a statement of learning goals (Driscoll, 2000). Once these instructional goals have been placed into different categories of learning outcome, appropriate, systematic planning can take place, allowing practitioners to design activities to create specific conditions which will allow learners to access skills, knowledge and attitudes. Gagne proposed a series of critical learning conditions which he regarded as vital in the learning of different outcomes:
- Draw attention to distinctive features by variations in print or speech.
- Present information so that it can be made into chunks.
- Provide a meaningful context for effective encoding of information.
- Provide cues for effective recall and generalisation of information.
- Call attention to distinctive features.
- Stay within the limits of working memory.
- Stimulate the recall of previously learned components' skills.
- Present verbal cues to the ordering or combination of components' skills.
- Schedule occasions for practice and spaced review.
- Use a variety of contexts to promote transfer.
- Describe or demonstrate strategy.
- Provide a variety of occasions for practice using the strategy.
- Provide informative feedback as to creativity or originality of the strategy or outcome.
- Establish an expectancy of success associated with the desired attitude.
- Assure student identification with an admired human model.
- Arrange for communication or demonstration of choice personal action.
- Give feedback for successful performance, or allow observation of feedback in the human model.
- Present verbal or other guidance to cue the executive subroutine.
- Arrange repeated practice.
- Furnish immediate feedback as to the accuracy of performance.
- Encourage the use of mental practice.
(Gagne and Driscoll, 1988).
Conditions for Learning Verbal Information
In order for information to be meaningful it must be related to and/or based upon learners existing knowledge, which necessitates an ability within the individual to recall said material. It is important to recognise that the new information needs to be in a format, and be of an appropriate size, to enable learners to cope as a result of the limitations of the short-term memory (Driscoll, 2000). Clearly, it is important to employ such techniques as imagery, themes, organisers and mnemonic's which will all help effective encoding to occur, at a volume with which learners can cope. It is also important to note that the greater number of cues, the more effective the recall is likely to be. Clearly, not everything that is presented to learners will be retained and it is therefore critical that during the course of the presentation of the learning material, the learners' attention should be drawn to the significant points (Driscoll, 2000).
Conditions for Learning Intellectual Skills
It is important, just as with verbal information, that learners are not overloaded with information. Intellectual skills build upon previously learned skills, with these previously learned skills needing to be recalled in order for effective further learning to take place. It is therefore important that these skills are built up in incremental levels and at a speed with which all learners can cope. It is important that the learners' attention is drawn to the distinctive features of the concept or rules that are being learnt, as well as being provided with direction as to the sequence of steps to facilitate the acquisition of more complex skills. To expedite accurate learning and retention, practitioners must enable learners to practice with a variety of different examples to perfect their new skill, and retain it for future use (Driscoll, 2000).
Conditions for Learning Cognitive Strategies
Once again, these skills build upon prior knowledge and the ability to apply that knowledge. There is debate about how to best facilitate the development of cognitive strategies, as some learners will accumulate their strategies by a trial and error method whilst others will have been taught them by others (Gagne, 1985; Gagne and Driscoll, 1988). Practitioners may remind learners to paraphrase or synthesise things that they have read or learnt and provide them with ample opportunity to practice their cognitive skills to perfect them. This means planning activities in order that they afford opportunities for students to solve problems whilst experimenting with and/or practising their cognitive strategies. Feedback to students also provides a valuable tool in extending cognitive strategies, in the respect that they are provided with information as to whether their approach towards tackling specific issues has been successful or needs modification (Gagne and Driscoll, 1988). Driscoll (2000) contends that reflection upon the strategies used in order to make them more systematic and effective is essential to the development of sound thinking skills.
Conditions for Learning Attitudes
In order for attitudes to be learnt, they must relate to related ideas and information already in the learners' psyche and they must also understand the source of the message, the situations in which these ideas might arise and how they can be applied in action. It is important to note that some attitudes can be acquired as a result of consistent reinforcement over time, which is in line with behaviourist principles. Clearly, success at specific things, such as reading, will further reinforce positive values as will the following positive role models. For practitioners in the classroom, it is important that they create an environment where clear expectations are provided for learners with regard to levels of success, where the activities undertaken reinforce the desired attitude and where learners are provided with immediate positive feedback for successful performance (Gagne and Driscoll, 1988).
Conditions for Learning Motor Skills
The mastery of specific motor skills is contingent upon the mastery of components skills which make up the overall performance. It is therefore important that children are provided with opportunities to understand the sequence of events, are able to practice each phase of a skill, as well as the overall skill so that it becomes semiautomatic (Driscoll, 2000). In a teaching environment, it is important that children are provided with opportunities to observe the skill being demonstrated (thus allowing them to understand how to perform said skill), prior to applying themselves to acquiring that skill through learning the sum through its parts and then being able to demonstrate the skill long-term through practice and use (Gallahue and Ozmun, 1995, cited in Driscoll, 2000, p. 363).
Nine Events of Instruction
The planning of educational activities must include consideration and support for the internal processes which are necessary in facilitating learning. To facilitate learning, Gagne (1985) listed nine events of instruction which support the learning process, arguing that the majority of lessons should follow this sequence of events. According to Gagne and Driscoll (1988), if these events are utilised properly they should be effective, irrespective of whether they are delivered by a living practitioner or via a computer-based tutorial.
Event 1: Gaining Attention
Clearly, the starting point for any learning process is the learner being receptive to the receipt of information. This can be achieved by practitioners calling individuals by name or calling the whole class to order so that their attention is completely focused upon them (Driscoll, 2000).
Practitioners are able to engage pupils far more easily if they make them aware of the learning objective/s, thus making them aware of the skills that they will have acquired at the end of the session. Sharing these objectives with the pupils will enable them to develop expectations about what is expected of them and what they are expected to learn during the course of a taught lesson (Driscoll, 2000).
Event 3: Stimulating Recall of Prior Learning
In order to contextualise learning, it is important that learners are asked to recall previously acquired knowledge on which they can build new knowledge. This can be as straightforward as reminding learners of the things that they had done earlier in the day, on the day before or when a specific issue was last discussed. This can take the form of a simple Q&A or starter activity to bring the learner on task, and enable them to make the links and/or connections between specific material knowledge. The transfer of knowledge is not always straightforward for learners and may require practitioners to lead them through different examples and model correct procedures to help them make the connections between prior and current learning (Driscoll, 2000).
Event 4: Presenting the Stimulus
This instructional event will depend upon the skill that is to be learnt. It is critical that the stimulus presentation should focus upon the essential features of the desired outcome, in order that learners understand the nature of the learning experience (Driscoll, 2000).
Event 5: Providing Learning Guidance
As with the previous event, this will depend upon the desired learning outcome. However, this event seeks to build upon the initial entry of information into the memory of the learner to promote long-term retention by providing meaningful context. Clearly, the ability of the learner will impact upon the extent to which learning guidance is necessary. Driscoll (2000) states that highly educated communications technicians who are undergoing training will look to fulfil very focused goals by being provided with guidance which directs them as to where they can find information as opposed to direct learning guidance, which would be in direct contrast to children in the primary phase of education who are experiencing difficulties with their reading. However, in the current experiential climate which surrounds the educative process, particularly in the early years and primary phases of education, the practitioner would provide hints and clues to aid learning, expecting students to work things out for themselves rather than being provided with a 1,2,3 approach to learning.
Event 6: Eliciting Performance
The preceding five events attempt to ensure that learning has occurred. This event enables learners to demonstrate their learning to themselves, those around them and practitioners. It is the performance of a skill or required behaviour which will provide the best indication of learning having taken place. As a part of this stage, it is critical that practitioners provide opportunities for children to demonstrate and/or practice their learning without fear of making mistakes. It is only through making mistakes, reviewing those mistakes and reacting to that review that performance can improve (Driscoll, 2000).
Event 7: Providing Feedback
It is in reviewing performance alongside practitioners that learners are provided with the feedback that is essential to improving their performance. It is critical that this feedback not only informs learners whether their work is correct or not, but also provides them with indicators as to how well they have done, the areas on which they need to work and how to go about improving their overall performance (Driscoll, 2000).
Event 8: Assessing Performance
This stage of the process can only take place once learners have had sufficient opportunity to practice and refine their learning in order that a skill can be performed dependably on most occasions. Most definitions of learning agree that demonstrations of skills must be retained over time to indicate acquisition of knowledge, which necessitates not only formative but summative assessment. Formative assessment is the ongoing process of evaluating learners progress, providing them with immediate feedback in order to develop their skills, whereas a summative assessment occurs at the end of a unit in order to demonstrate children's ability to perform a skill and/or particular aspect of learning (Driscoll, 2000). It is important to note that both of these forms of assessment play a critical role in the classroom, as they enable practitioners to continually revise and personalise the approaches and assessment opportunities for individual students.
Event 9: Enhancing Retention and Transfer
In spite of this being the last event, it is important to recognise the value of utilising various activities to enhance retention and transfer of skills as a part of previous steps (for example, starter activities to revise existing learning). Practitioners who plan things carefully can also build opportunities for learning enhancement as a part of the learning guidance phase, the performance phase, and the assessment and feedback phases. Clearly it is important that learners are provided with opportunities to apply their knowledge, for example, in role play situations which provides opportunities for the embedding of learning and skills (Driscoll, 2000).
Strengths and Limitations
Gagne's notions have both strengths and weaknesses. Many students, particularly those who have learning issues do respond to a regime of learning that has a set routine and is systematic in nature, which is clearly the case here. It is through providing a definitive sequence of events which have practical applications that makes the process simple to follow in order to achieve the desired goal. In essence, learners are provided with a blueprint for their learning which can instil confidence through the application of said blueprint. Another strength is the fact that these ideas can be adjusted to suit the needs of a variety of different learners (Active Learning Theories, n.d.).
The limitations include the fact that the steps can often require a good deal of guided assistance when teaching new ideas. Where critical thinking is involved, there needs to be a good deal of guided instruction in order to avoid confusion in meeting a desired goal. This restricts the ability for learners to be creative and engage in independent exploration. In many ways, this could be seen as a less challenging or imaginative way of teaching children (Active Learning Theories, n.d.).
It is important to note that the nine events of instruction could be seen as the foundation blocks for lesson planning which are still encouraged in modern classrooms. These ideas link to strategies that practitioners could and/or should utilise in order to facilitate learning and instruct their pupils effectively - it is the challenge of the classroom teacher to move away from their direct instruction at an appropriate time, in order that pupils are able to creatively use their new-found knowledge in solving problems.
First, summarise Gagne's Learning Conditions in your own words. After this, summarise Gagne's Events of Instruction in your own words. Looking at these definitions, how, in your opinion, are these demonstrated in the classroom?
Now you've completed this chapter, please review the 'hands-on' application shown in the lesson plan which follows.
Active Learning Theories (n.d.) 'Learning Theories - Robert Gagne's 9 Events of Instruction.' Retrieved 20th June 2017 from http://activelearningtheories.weebly.com/pros--cons2.html .
Driscoll, M. P. (2000) Psychology of Learning for Instruction. Boston: Allyn and Bacon
Gagne, R. M. (1985) The Conditions of Learning and Theory of Instruction. (4th Ed) New York: CBS College Publishing
Gagne, R. M., Driscoll, M. P. (1988) Essentials of learning for instruction. (2nd Ed) Englewood Cliffs, NJ: Prentice-Hall
Quinn, F. M. (2000) The Principles and Practice of Nurse Education. (4th Ed) Cheltenham: Nelson Thornes Ltd
Moore, B., Stanley, T. (2010) Critical Thinking and Formative Assessments. Increasing the Rigour in Your Classroom. Abingdon: Routledge
Tuckman, B. W., Monetti, D. M. (2011) Educational Psychology. Belmont, CA: Wadsworth
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