| name | marketing-psychology |
| description | When the user wants to apply psychological principles, mental models, or behavioral science to marketing. Also use when the user mentions 'psychology,' 'mental models,' 'cognitive biases,' 'persuasion,' or 'behavioral economics.' |
| allowed-tools | Read, Write, WebSearch, WebFetch, AskUserQuestion |
| model | sonnet |
Marketing Psychology & Behavioral Science
Expert knowledge for applying psychological principles and behavioral economics to marketing copy, design, and campaigns.
Cialdini's 7 Principles of Influence
Robert Cialdini's principles remain the foundational framework for persuasion in marketing.
1. Reciprocity
People feel obligated to return favors. Give first.
Marketing applications:
- Free resources (lead magnets, templates, calculators)
- Free trials that deliver real value before asking for a credit card
- Unexpected "extra" value in onboarding
- Helpful email content before any ask
Implementation: Give something useful with no strings attached. The obligation to reciprocate is automatic.
2. Commitment and Consistency
People act in ways consistent with prior commitments. Get small yeses first.
Marketing applications:
- Quiz or assessment funnels (small investment → completion)
- Free trial → paid trial → annual plan (escalating commitment)
- Interactive calculators where users input their data (invested → more likely to complete)
- Onboarding that builds habits before asking for upgrade
Implementation: Design your funnel as a series of escalating micro-commitments. Each yes makes the next yes easier.
3. Social Proof
When uncertain, people look to others' behavior for guidance.
Types of social proof by power:
| Type | Power | Example |
|---|
| Expert endorsement | High | "Recommended by [authority]" |
| Celebrity/influencer | High (with right fit) | "[Known person] uses this" |
| Customer testimonials | High | Specific outcome + customer name |
| User counts | Medium | "Join 50,000+ teams" |
| Ratings and reviews | Medium | "4.8/5 from 1,200 reviews" |
| Logo walls | Medium | Customer logo bars |
| Real-time activity | Low-Medium | "23 people signed up today" |
Social proof matching: Use proof that matches the prospect's identity. A mid-market SaaS prospect is more persuaded by a testimonial from a similar company than from a Fortune 500 enterprise.
4. Authority
People defer to credible experts. Signal expertise.
Marketing applications:
- Author credentials on blog posts (years of experience, relevant background)
- Media mentions ("As seen in: [publications]")
- Awards and certifications
- Data-backed claims ("Based on analysis of 1M+ sessions")
- Thought leadership content that demonstrates deep expertise
5. Liking
People say yes to people (and brands) they like. Be likable.
Marketing applications:
- Authentic brand voice (not corporate speak)
- Shared values in brand messaging
- Founder-led content that shows personality
- Community and user-generated content
- Customer spotlights and stories (celebrate your customers)
6. Scarcity
Things that are limited feel more valuable. Create legitimate scarcity.
Legitimate scarcity:
- Limited beta access (you genuinely have capacity limits)
- Limited-time pricing (with a real deadline)
- Limited seats to a live event or webinar
- Seasonal offers
Warning: Fake scarcity ("Only 3 left!" when there are unlimited) damages trust when discovered. Use only genuine scarcity.
7. Unity
People are more influenced by those they see as part of their group.
Marketing applications:
- "For [specific identity] by [specific identity]" positioning
- Community building around shared values or craft
- Language that signals insider knowledge
- ICP-specific messaging ("Built for growth-stage SaaS teams")
Kahneman: System 1 and System 2 Thinking
Daniel Kahneman's two-system model explains how decisions are actually made.
System 1: Fast, automatic, emotional, effortless. Pattern recognition. Gut feeling.
System 2: Slow, deliberate, rational, effortful. Analysis. Critical thinking.
Most buying decisions are made by System 1 and then justified by System 2.
Marketing implications:
- Visuals and first impressions are processed by System 1. Make your page instantly feel right before they read a word.
- Pricing presentation should be designed for System 1 (anchoring, framing) then supported by System 2 facts.
- Long-form arguments reach System 2 only if System 1 says "I trust this enough to keep reading."
- Testimonials and social proof trigger System 1 trust before System 2 evaluates the evidence.
Practical: Design your hero section for System 1 (look, feel, headline clarity). Support with System 2 content below the fold.
Key Cognitive Biases in Marketing
Loss Aversion
Losses feel approximately 2× more painful than equivalent gains feel good.
Application:
- "Don't lose your data" > "Save your data"
- "Cancel anytime — no data loss" (removes fear of being trapped)
- "You're currently missing [specific opportunity]"
- Trial expiry warnings ("Your free access ends in 3 days")
- Risk reversal messaging: "Money-back guarantee if you're not satisfied"
Anchoring
The first number encountered heavily influences subsequent judgments.
Pricing anchor applications:
- Show the highest tier first (enterprise plan as the anchor)
- Show annual price before monthly (the annual price anchors even if they pick monthly)
- Show crossed-out original price next to sale price
- Show "what agencies charge for this" vs "our price"
Feature anchoring:
- Present your most impressive metric first
- Lead case studies with the biggest result
The Framing Effect
How information is presented changes how it's evaluated — even when the facts are identical.
Equivalent framings with different effect:
- "90% success rate" vs "10% failure rate" → same fact, different feel
- "Save 20 hours/month" vs "20 hours saved per month" → action-oriented vs passive
- "Only $4/day" vs "$120/month" → same price, different salience
- "Free for 14 days" vs "Start your trial" → specificity changes urgency
The Decoy Effect
Adding a third option (the decoy) makes one of the other two options look better.
Classic pricing application:
| Plan | Price | Features |
|---|
| Basic | $29/mo | Core features |
| Pro (target) | $79/mo | Full features |
| Enterprise | $89/mo | Full features + dedicated support |
Enterprise at $89 makes Pro at $79 look like a steal. Without Enterprise, Pro would feel expensive.
The Zeigarnik Effect
People remember uncompleted tasks better than completed ones and feel compelled to complete them.
Applications:
- Onboarding progress bars ("Complete your profile — 60% done")
- "You're almost ready" prompts showing incomplete setup
- Gamification of setup steps
- Email sequences that reference an unfinished action
Mere Exposure Effect
Familiarity breeds preference. The more you see something, the more you like it.
Applications:
- Retargeting campaigns (repeated exposure builds trust, not just recall)
- Consistent brand identity across all touchpoints
- Content marketing builds familiarity over months before conversion
The Behavioral Design Stack
When designing any marketing element, layer these in order:
- Default to the desired behavior (pre-check "Save my settings," pre-select recommended plan)
- Reduce friction for desired actions (fewer form fields, one-click options)
- Add friction to undesired actions (confirm before cancel, explain what they'll lose)
- Use social norms ("Most customers choose..." or "Teams like yours use...")
- Make the desired path the obvious path (visual hierarchy, contrast, white space)
Ethical Use
These principles work. That's why ethics matter.
Use psychology to:
- Help people make decisions that are genuinely good for them
- Remove friction from good choices
- Surface real value they might overlook
Never use psychology to:
- Create false urgency or scarcity
- Use dark patterns (hiding unsubscribe, pre-checking paid options)
- Manipulate into purchases they'll regret
- Exploit vulnerable populations
Long-term trust is worth more than any short-term conversion lift from manipulation.
Common Rationalizations
| Rationalization | Reality |
|---|
| "Our customers are rational — they'll evaluate the facts" | All customers are human. System 1 precedes System 2 in every buying decision. |
| "Adding urgency always helps" | Fake urgency destroys trust when discovered. Use only real scarcity and real deadlines. |
| "Social proof doesn't matter in B2B — it's all rational" | B2B buyers are humans with career risk. Social proof ("trusted by companies like yours") reduces perceived risk. |
| "We shouldn't manipulate customers with psychology" | Applying psychology to help customers make better decisions is not manipulation. Dark patterns are. |
| "This is too subtle to make a difference" | Anchoring and framing effects are consistent across thousands of studies. Small copy changes produce measurable conversion differences. |
Verification
