Two Brains in One Head: Why Proposals Need to Persuade Both Fast and Slow Thinking 

We Don’t Just Read with One Brain 

Every proposal evaluator is really two readers at once. Two brains in one head. 

Neuroscience tells us that our eyes send information along two pathways: 

Magnocellular (Magno):

fast, instinctive, contrast-driven, big-picture. 

Parvocellular (Parvo):

slow, detail-oriented, color- and logic-driven. 

This is  very similar to Daniel Kahneman’s famous persuasion model: 

System 1 (Magno):

fast, emotional, intuitive. 

System 2 (Parvo):

slow, rational, analytical. 

When someone reads your proposal, they’re doing both. A quick gut-check skim. Then a slower, point-by-point score. 

The balance might be different in each reader. But, to win, you need to persuade both brains. 

The Skim vs The Score 

First comes the skim. Headings. Summaries. Pull quotes. The evaluator is tired, pressed for time, juggling ten proposals at once.

They’re asking: 

“Does this feel credible? Is it worth reading on?” 

Then comes the score. Out comes the criteria. Each section is checked against compliance, evidence, detail.

The evaluator is asking: 

“Does this hold up? Is it proven? Does it meet the brief?” 

Great proposals work in both modes. They’re clear, compelling stories and evidence-rich documents. 

Why Structure Is Strategy 

This is why winning proposal teams always storyboard before they write. 

Structure isn’t cosmetic, it’s cognitive. Headings, hierarchies, visual cues: they reduce cognitive load and guide both fast and slow reading. 

And accessibility?

That’s not a compliance box to tick. It’s persuasion strategy. Plain language, clear structure, logical flow all make life easier for evaluators. And making life easier makes your proposal more persuasive. 

The Two Questions Every Proposal Must Answer 

Think of it like this: 

1. Magno Mode (System 1):

At first glance, does this feel credible, compelling, and worth attention? 

2. Parvo Mode (System 2):

Under scrutiny, does it stand up against the criteria with evidence in the right places? 

Answer “yes” to both, and you’ve got a strong chance of winning. 

Could AI Help Us Balance Both Brains? 

Here’s the provocation. 

What if AI could help test your proposals against these two modes of reading? Not to replace evaluators, but to simulate their perspectives. 

The Magno Test (Skim-Reader Mode):

Feed in headings, exec summary, pull quotes. Ask AI: what’s the impression? Is it clear? Compelling? Worth reading on? 

The Parvo Test (Scorer Mode):

Feed in the full narrative plus evaluation criteria. Ask AI: how would you score this? What’s missing? Where’s the evidence thin? 

Together, you’d get a dual perspective: gut feel and mark scheme. 

At AutogenAI, we’re already experimenting with similar questions through tools like Gamma Review and Ask AI. Could testing proposals through both “brains” become part of the craft? 

Why It Matters 

Because proposals aren’t just documents. They’re decisions on paper. 

Lose one brain and you lose the reader. A proposal that looks good but collapses on detail? Fail. A proposal that’s watertight but unreadable? Fail. 

The winners are the ones that move seamlessly between fast and slow, skim and score, Magno and Parvo. 

Where Next? 

We haven’t cracked it yet, but we’re starting to see the shape of it. 

At AutogenAI, we’ve built more than 60 proprietary benchmarks that already test proposals against the things evaluators prize: compliance, clarity, evidence, tone. Our Gamma Review feature can surface where a response falls short. The Williams-Huckle Benchmark is even being used by frontier AI labs to help train their models. 

So perhaps the next frontier isn’t just better drafting, but better reading. AI that can mimic the two brains in one head, skim-reader and scorer, and give us feedback from both. 

Because that’s the real challenge. Every evaluator is two readers at once. And every winning proposal has to win them both. 

Book a demo with AutogenAI to streamline your bid process.