Moving Beyond the Summary: How to Synthesize Literature Rather Than List It

The literature review is the section of the dissertation that separates authors who have read widely from authors who have thought carefully about what they have read. The difference is synthesis.

Synthesis is a cognitive technique before it is a writing technique, and no rearrangement of summaries into a better order will produce it, however careful the rearranging. It comes from understanding the conversation the sources are having with each other. Then you write about that conversation.

Most early-draft literature reviews are annotated bibliographies in prose form: a series of paragraphs, each devoted to a single source, each following approximately the same structure — the author argued this, the study found that, the limitation was the other thing. As a first pass, this is useful. It shows that the author has read the sources. What it leaves undemonstrated is the engagement a dissertation committee is actually evaluating: how the sources relate to each other, where they agree, where they diverge, what questions they collectively leave open, and how the current study is positioned to address those questions.

Synthesis begins with a different organizing question. Instead of "What did each source say?" the question becomes "What does the literature, taken as a whole, establish, contest, and leave unresolved?" The answer generates a framework — a set of themes, tensions, or debates — that the literature review then uses to organize the sources. Sources are grouped by the claim or question they bear on most directly, whatever their publication date or authorship, and each one appears within the framework in service of the argument the framework is making.

The practical steps. Before drafting the literature review, read through all of the sources and identify the recurring themes: the questions that multiple sources address, the points of consensus, and the points of genuine disagreement. Map these themes. Identify which sources belong to which theme and what each source contributes to the theme's development. Then draft the review as a series of thematic sections, each making a claim about the state of the literature on its theme and using specific sources as evidence for that claim. Taken together, the sections should position the current study as a logical and necessary response to what the existing literature has and has not accomplished, which is the purpose of the whole section.

The citation pattern is diagnostic. A synthesized literature review cites multiple sources within single sentences and paragraphs, because its sentences and paragraphs make claims about the literature as a whole. A source-by-source summary cites one source per paragraph. Each paragraph is about one source. If every paragraph in your literature review has exactly one citation, the review is probably not yet synthesized.