Horizontal Logic
With respect to overall structure, a good deck will usually exhibit two different kinds of logic:
- Horizontal Logic, which refers to the overall coherence of the story from one slide to another. Do action titles, when read in sequence, tell a clear and logically-articulated story?
- Vertical Logic, which refers to the internal coherence of a given slide. Is the action title supported by the body slide? Does the evidence presented support the overall message?
I am using a deck I helped put together a few years ago, for illustration. The content is long out of date, but it’s a decent example that I happened to have on hand.
Ignore Slides 1 through 8, which are just my then-employer’s corporate boilerplate. The story we are telling really begins on Slide 9. From then on, each of the action titles can be read out in sequence to form a story.
In fact, with the addition of a few filler words (in bold), one could almost imagine reading the action titles (and section titles) aloud as a speech of some kind:
- (The big question is) How did European PCR companies perform in 2012?
- (It turns out that) In 2012, a protracted low growth environment and continued overcapacity problems weighed on petrochemical margins in China
- European PCR companies (in particular) were not spared – while more companies reported rising revenues, margins also appeared to fall
- (Interestingly) Companies are more optimistic about future growth than profitability – shrinking margins may become part of business-as-usual
- And so and and so forth…
If the resulting story flows logically and naturally and conveys key messages clearly, then chances are the horizontal logic is solid.