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HBDI® Whole Brain® Profile

Two strong quadrants

A short, honest look at a thinking-preference assessment I've found genuinely useful: what it measures, what it doesn't, and where my own profile lands.

What HBDI actually is

The Herrmann Brain Dominance Instrument was developed by Ned Herrmann at GE in the 1970s, drawing on Roger Sperry's split-brain research and Paul MacLean's triune-brain model. It sorts thinking preference, not ability, into four quadrants: analytical, practical, relational, and experimental. You take a self-report questionnaire; it comes back as a profile of which quadrants you gravitate toward, not how skilled you are in any of them.

Two things are worth saying plainly. It's a preference model, not an IQ or competency test, so a "strong" quadrant means you default there, not that you're better at it than someone whose default sits elsewhere. And it's a proprietary instrument, still widely used in corporate leadership-development programs, which is where I first took it.

My profile

Strong preference in two quadrants that sit diagonally opposite each other: analytical and experimental. Practical and relational are both present, just intermediate rather than dominant.

63%
37%
Analytical + Experimental (upper, cerebral)Practical + Relational (lower, limbic)

These are the instrument's own reported figures, not an independent statistical measurement — treat them as "roughly two-thirds / one-third," not as precise to the point.

Analytical

1 · Strong

Logical, fact-based, quantitative. Wants to know what the data actually says before deciding anything.

Where it shows up: the statistical rigor behind the county valuation work — COD, PRD, ratio studies, model-blind validation gates.

Experimental

1 · Strong

Conceptual, big-picture, comfortable with novelty. Wants to build the thing that doesn't exist yet.

Where it shows up: designing and shipping a library of AI agent workflows from scratch, and being willing to kill one that isn't earning its keep.

Practical

2 · Intermediate

Organized, sequential, detail-oriented. Cares about getting the thing actually done and documented.

Where it shows up: present but secondary — it's the difference between a good idea and a change-order gate that actually stops unfunded work, or a QC check that catches a corrupted file before a client sees it.

Relational

2 · Intermediate

Interpersonal, expressive, teaching-oriented. Reads the room and the relationship, not just the numbers.

Where it shows up: also secondary, also real — it's the part of me that ended up running a real estate club for nine regional chapters instead of just investing on my own.

In Herrmann's own language this is a "double-dominant" profile: two strong quadrants that sit diagonally across the model rather than next to each other. In practice, it means my default mode swings between rigor and reinvention, with execution and people-work as real but secondary strengths I lean on deliberately rather than by instinct.

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