Analysis involves the exploration of relationships, looking for patterns in the information available, and the classification of objectives. Analysis is the ordering and structuring of the problem. Synthesis on the other hand is characterized by an attempt to move forward and create a response to the problem – the generation of solutions. Appraisal involves the critical evaluation of suggested solutions against the objectives identified in the analysis phase.
A complete picture of design method requires both a ‘decision sequence’ and a ‘design process’ or ‘morphology’. They suggest that we need to go through the decision sequence of analysis, synthesis, appraisal and decision at increasingly detailed levels of the design process (stages 2, 3, 4 and 5 in the RIBA handbook) (…) Maps of the design process may need to allow for return loops from an activity to that preceding it (…) This accounts for the return loop in the Markus/Maver decision sequence from appraisal to synthesis, which in simple terms calls for the designer to have another idea since the previous one turned out to be inadequate.
Lawson, B., 2005. How Designers Think: The Design Process Demystified (4th ed.). Oxford: Architectural Press
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