Causality Bias
Why people assume one event caused another just because they happened in sequence, and how to use causality bias in your marketing.
In this issue
Happy Thursday.
Last week, we wore our lucky socks and our open rates went up.
Coincidence? Absolutely. But try telling that to our brains, which are already knitting a second pair.
The thing is, humans love connecting dots, even when the dots are just… dots. That’s what we’ll talk about in today’s issue.
Reading time: 4 minutes, 42 seconds
What if doing nothing beat 90% of professional fund managers?
The investment industry sells complexity. Research. Timing. Alpha.
The data tells a different story. Over any 20-year period, a simple world index fund has outperformed more than 90% of professionals. Most investors who try to beat the market end up paying more in fees to underperform it.
The edge isn’t intelligence. It’s patience.
But patience is hard when your portfolio feels abstract. A passive fund is just a ticker on a screen. The thousands of companies inside it, the businesses you actually co-own, stay invisible.
90 Percent fixes that. Every week, it pulls one company at random from the world equity index and tells you what it actually does.
- The Brazilian company that makes the electric motors inside almost everything that spins.
- The Florida company that sells your airline its spare parts at half the price.
- The Japanese hardware company hiding inside every factory.
One company. Every week. Yours to discover.
You restarted your laptop. The Wi-Fi came back.
Was it the restart? Or the signal just came back at the same time? You don’t know. But you’ll restart your computer to fix Wi-Fi every time now.
That’s Causality Bias at work. Also known as the illusion of causality.
It’s our tendency to believe one event caused another when the two are, in reality, completely unrelated.
Research published in Frontiers in Psychology found these illusions can happen to anyone under the right conditions and they fuel superstition, pseudoscience, and the likes.
The recipe is simple. Something happens often, eg. you take a pill daily. A desired outcome happens often too—say, you feel more energetic. Even though it might just be a placebo.
But your brain stamps “cause” on the coincidence.
You took it. You got better. It works. Science calls that an illusion. Your customer calls it proof.
And it’s everywhere:
- The 9 AM post that “made” your reel go viral.
- The vitamin C that “cured” your cold.
- The standing desk that “fixed” your focus.
Our angle: People don’t wait for proof of causation. They manufacture it from sequence and repetition.
Give their brains the right sequence, and they’ll write the causal story for you.
Three ways to leverage Causality Bias
Structure testimonials as before-and-after stories
Nothing triggers causality bias like a timeline.
“Before I found this product, X. Since I started using it, Y.” The reader’s brain fills in “because” automatically. It doesn’t need no claims.
AG1 built an empire on this. Their testimonials and creator ads follow one script: “I drink it every morning, and my energy improved.”
No clinical causation is stated. The day-after-day sequence implies it.
Your move: collect testimonials describing life before the product, the moment of adoption, and the change after. Sequence sells the causation your legal team won’t let you claim.
Publish case studies with timelines and numbers
B2B’s favorite causality machine? The case study.
“After switching to HubSpot, this brand grew 300% in six months.” Did HubSpot cause all of it? New hires, market shifts, and luck helped too.
Doesn’t matter. The after-plus-timeline-plus-number combo makes readers infer pure causation.
Shopify, Slack, and other B2Bs run the same play: customer stories built around a switch date and a growth metric.
Your move: anchor every case study to a specific “after we implemented” moment and one hard number. The tighter the timeline, the stronger the perceived cause.
Build a ritual around your product
Rituals are causality bias in a costume.
Repeat a sequence—action, then enjoyment—and the brain concludes the action causes the enjoyment.
Oreo’s “Twist, Lick, Dunk” turned a cookie into a procedure. Corona made the lime wedge non-negotiable. Guinness convinced the world a 119.5-second pour tastes better.
Does the ritual change the product? Barely. Does it change the experience? Completely.
The ritual becomes the “cause” of the pleasure—and your product becomes irreplaceable in the sequence.
Prescribe exactly how to use, consume, or apply your product. A branded ritual is a causal story customers perform daily.
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Thursday’s idea, live at lunch. No code, no queue. You publish to a real link during that workshop.
You keep the skill. The prompts and the know-how are yours for next time.
Join us and AI for Work for the next workshopon 5th July, from 12pm ET.
META: …just launched Muse Image, its first in-house image model, live in Meta AI now.
It’s a prompt-driven creative engine that renders legible text and even functional QR codes. The best part? It’s coming to advertisers through Advantage+ creative. Worth a test drive.
TIKTOK:Streaming ads? Yep. You can now pair high-intent users with specific titles from a streaming catalog and turn idle scrolling into signups on TikTok. Smart+ handles the bidding and optimization, so you can focus on strategy. Nice.
REDDIT:What if you have a bot problem? You bring more bots to clean up. Reddit says its upgraded AI defenses are cutting spam exposure and revoking nearly 2M fake votes daily.
Suspicious automated accounts now get asked to verify their humanity. Interesting.
NETFLIX: Starting August 3, the platform brings web-native shorts from BuzzFeed, Condé Nast, Hearst, and Penske brands to subscribers in the US, Canada, UK, Ireland, Australia, and New Zealand. It’s a cheap test of whether bingers crave YouTube-style content on Netflix too.
ICYMI, last time we looked at the Confirmation Bias.
The “Lucky Socks” Crew.
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