kennethreitz
ce93f429a2
Publish the Obsidian vault's Knowledge folder as /knowledge (881 notes, 67 folders), with a Knowledge item in the nav and footer. - scripts/import_knowledge.py regenerates data/knowledge from the vault: slugged paths, folder notes as index pages, wikilinks resolved to site links (or plain text), callouts, highlights, and Dataview tables rendered statically. Personal notes are withheld via an exclusion list plus a privacy guard. - tuftecms/core/knowledge.py builds a concept index from note titles and aliases. First mentions on ordinary pages link to their Knowledge note (capped, never in headings, code, links, or sidenotes); Knowledge pages list related notes and where they're mentioned across the site; other pages get a Related Knowledge block. - Knowledge URLs join sitemap.xml (so the sweep test covers them), never displace existing legacy slugs, list alphabetically, and mermaid diagrams render client-side only on pages that have them.
2.5 KiB
description, source
| description | source |
|---|---|
| You expected the front door. It comes in through the back. | obsidian-knowledge |
Backdoor Progression
You expected the front door. It comes in through the back.
The Progression
The backdoor progression is a jazz substitute cadence: ii–♭VII7–I, where a dominant seventh built on the flatted seventh degree stands in for the usual V. In C the expected G7 is replaced by B♭7, and that chord resolves up to Cmaj7 not through a leading-tone pull but through a smooth, unexpected side entrance — hence the name. The ♭VII7 shares tones with the tonic that make its arrival feel warm and inevitable rather than jarring.
The trick lies in voice-leading. B♭7 contains the notes A♭ and D; as it resolves to Cmaj7, A♭ falls to G and D holds or rises to E, gliding the ear home from an angle it did not anticipate. It borrows the flavor of the IV minor world — the ♭VII7 functions like the dominant of a borrowed subdominant — giving the resolution a soulful, gospel-tinged softness that a straight V–I cannot.
Structure
| Attribute | Value |
|---|---|
| Roman numerals | ii – ♭VII7 – I |
| Example in C | Dm7 – B♭7 – Cmaj7 |
| Chords used | Minor Seventh (ii), Dominant Seventh (♭VII7), Major Seventh (I) |
| Character | Warm, unexpected, soulful |
| Function | Predominant → backdoor dominant → tonic |
In Practice
It colors jazz, soul, and gospel harmony — Steely Dan, Stevie Wonder, and countless standards slip through this backdoor to soften a turnaround or dodge a predictable cadence. Arrangers reach for it when a plain ii-V-I feels too direct and a bit of shadow is wanted. It sits within the broader logic of the Circle of Fifths Progression and the substitute Cadences.