What did you learn at Cohort 12 of Visual Thinking Workshop? Interview with Iwan Hoogendoorn

Cohort 12 participant Iwan Hoogendoorn built a tightly integrated workflow in Obsidian and Excalidraw to turn dense reading—especially “The Lessons of History” by Will and Ariel Durant—into a set of visual, searchable, and repeatable learning artifacts. The core payoff is practical: he can navigate his life and his study topics through a visual “dashboard,” then convert each chapter into icons, diagrams, and highlighted takeaways that make the book’s message easier to remember and easier to act on.

Hoogendoorn’s system starts with Obsidian as the central memory for a busy, multi-domain life. He already used Obsidian for years after moving through Evernote, Bear, and Notion. What changed after joining the Visual Thinking Workshop was the ability to create drawings inside Obsidian and link them back to existing notes. That integration—rather than bouncing between separate tools—made the workflow “come together,” especially for people who find both Obsidian and the visual-thinking approach daunting at first.

For the course, he created a “course outline” note that functions like a planning dashboard: a single long note with a table of main topics, video lengths, and homework estimates. He tracked the time burden honestly, noting that the homework—around 79 hours in his estimate—felt the hardest part, even if the estimates were broadly accurate. He also imported the book’s PDF into his Obsidian vault so every chapter and page could be reached with one click.

His reading-to-visual pipeline is iterative and granular. He reads chapter-by-chapter, and within each chapter he processes highlights and produces a visual after each paragraph. He imports the PDF pages into Excalidraw, then uses PDF highlighting as a way to pinpoint what matters. Those highlights aren’t copied text; they become transparent overlays that guide what he turns into diagrams.

To overcome difficulty with complex language and to speed comprehension, he uses ChatGPT as a companion: first to generate a one-sentence or one-word summary of a chapter, and later to produce explanations “like I was 12 years old.” When he still needs direction, he prompts for multiple illustration ideas and then chooses the one that best matches the chapter’s message. This approach helps him translate abstract historical themes into concrete visual metaphors—such as different “versions of history” depending on what lens a person uses (technology, music, leadership, and more).

Hoogendoorn argues that visuals outperform paragraph-only notes for recall and understanding. Looking at a diagram gives an immediate sense of the chapter’s takeaway, while written paragraphs require more reading time to locate meaning. He also emphasizes curation over artistic skill: simple icon choices, consistent color rules, and repeated visual motifs (like lines indicating movement) are enough to make the result personal and effective.

Finally, he recommends the workshop broadly but with a clear expectation: it demands effort to learn the tools (Obsidian, Excalidraw, and the workshop’s visual thinking framework). The reward is a method that can be reused across life domains—work, music practice, DJing, and more—by building visual “maps” that keep knowledge navigable over time.