For the purposes of this graphic, only value over .4 are included, after all every paragraph receives 30 scores, we don’t need the bottom of the graphic entirely crowded. You can see the tightening in second Inaugurals, as there is no difference to mark from the prior administration. To quantify this shift, we would need to look at the average assignment value, total number of assignments, and assignments per word.
Topic 11 is the most frequently assigned. Special outliers here include Nixon’s rhetoric on the end of the Vietnam war framed as Peace (29), save an aggressive Trump paragraph. Topic 30 are benedictions and claims of devotion to America, a central theme for Biden, where a typical President may make one or two.
Second Inaugurals tend to have higher average assignment values with higher maxes (Obama is a bit of an outlier here), which would again suggest that the second speech is more focused. In this sense, Biden is reading more like a second inaugural, although his very high max scores come in topics 11, 16, and 30 where Biden’s signature theme of devotion to America comes across quite clearly. JFK uses topic 11 then topic 26, a foreign policy topic employed by many others, but only detected once in the work of George W. Bush. This would make sense as his first was pre-9/11, but his most powerful statements on Foreign Policy are in topic 8 — as they are couched in the language of Rheinhold Niebuhr, classical realism — they are matters of the soul. This would also confirm something else: there is no foreign policy driven Inaugural, aside from the language of cooperation in topic 26, foreign policy matters are couched in American civil religion.
We can confirm with this method that Obama’s first was about topic 11, but then topic 21 — a topic about the journey to overcome binaries. 60% of all topic 21 locations are from Obama’s first, with two uses by Nixon1, and single paragraphs by Reagan2 and Clinton1. The use by Reagan is especially interesting as it is a long form mixed metaphor about the idea of history ending: “the song echoes out forever and fills the unknowing air.”
Finally, it is important to consider the rate at which topics are detected.
Biden’s speech was quite long and had more topics than average, and a rate of topic detection near average. Aside from Obama, each second speech dwells more than that which came before. Of course there is one dramatic outlier, which we have established is different in kind from the others.
Conclusion
The rhetorical signal of the Inaugural by President Biden conforms to expectations both in topic selection and variation. The topic modeling process further would suggest that aside from the standard frame (the future promise of the country), detected as topic 11, Biden’s speech contributes a unique signature to the corpus through the topical focus on devotion to America and democracy. While it is entirely possible that readings will change, in the context of this initial machine learning driven approach and rhetorical reading of those results, it is clear that President Biden delivered an address that is quite true to the form of the Inaugural and well-suited to the moment. Finally, we can clearly see the evidence supporting the long history of speech research on the Inaugural laid out graphically.