confirmation bias psychology — 1 thorough investigation

confirmation bias in psychology gets its own dedicated chapter, its own foundational studies, and its own quiet warning labels in every textbook. mine gets the corner of a small notebook and a poorly drawn picture of mike pointing across a bar table. the published literature is more thorough overall. the drawing, frankly, is more accurate to my situation.

i’m typing this from my own apartment for once, which is a clerical anomaly i’ll explain in two sentences and then drop. the office building has a power-down between 9:47am and the rest of the morning while they replace something on the third floor, so carla is technically in the all-hands at a satellite location and i am, technically, on standby at the kitchen counter with a laptop and the seventh microwave humming three feet away. that is the entire deviation from canon. note it, file it, do not write to me about it.

so. confirmation bias psychology. that’s what the search engine sent you here for. the word “psychology” attached to it is what makes the topic feel official — the kind of phrase that appears on a slide deck before a budget conversation. i’m going to take the phrase apart anyway. the full investigation of confirmation bias as a working concept is in the cluster pillar, where i did the slow version. this post is the shorter, louder one, with mike in it.

confirmation bias psychology, the short version

here is the short version, because nobody who searched “confirmation bias psychology” actually wanted the long version. they wanted a sentence to put in a slide. i’ll give you the sentence and then i will, in classic fashion, give you the rest anyway.

the sentence: your brain treats your existing belief as the home team and treats incoming evidence as either a fan or a heckler. the fans are waved through. the hecklers are reviewed for a polite minute, found unconvincing, and asked to leave. you did not authorize this. it happened. the report on the matter is, conveniently, written by the same brain that did the filtering.

the word “psychology” in the phrase carries a particular weight. it implies labs. it implies labcoats. it implies that somewhere, a person with a clipboard is making sure this is rigorous. and i’m fairly sure there is, in the literature i am sure exists, an actual foundational paper about it from the sixties or seventies, where the experimenters showed two groups the same article and both groups walked out more convinced of opposite positions and both groups described the article as biased against them. that is the species. that is us. i did not read the paper. i agreed with the summary on contact, which is, structurally, the joke.

the textbook treats the topic as a curiosity. a wrinkle. a side effect. in my apartment, surrounded by the residue of years of being confidently wrong, i treat it as the operating system. the textbook is being polite. i am not.

the take i defend in this matter

here is where i plant the flag. i hold one strong opinion in this whole conversation and i am going to defend it loudly, in proper pulpit form, with the volume turned up because the apartment is empty and nobody can shush me from the third floor.

mike heard me defend it, allegedly

i tested the take on mike, last week, at the corner, on a tuesday around 9pm, before he’d had his second. the timing matters. mike pre-second-beer is a different epistemology than mike post-third. the muted simpsons were on the tv above the bar, as is canon. i told mike what i was going to write about. mike, on this occasion, listened.

i said: “mondays beat fridays. the data is clear if you collect it honestly.” mike took a slow sip and said, without looking at me, “your data is your apartment. you collected it from your couch.”

which, fairly. but i pressed on. “friday-me,” i said, “is always disappointed. friday-me thinks the weekend will fix things. monday-me has no such illusion. monday-me is calibrated. monday-me is, in fact, the most sober version of me that exists in any given week.”

mike said, “that’s confirmation bias by someone who is already always right.” which was, structurally, a compliment, and also the kind of thing a comfortable liar says about himself when challenged on a tuesday. the word liar gets thrown around at the bar more than it should — mike uses it about politicians, about landlords, about himself when he says he’s “almost done” with anything. mike, for the record, has not filed his taxes since 2019. mike has earned the right to use the word.

then mike said the part i actually wrote down. mike said: “the brain rounds up. it rounds up to i was right, i am right, i will be right. it does this to keep you safe. it doesn’t care that the only predator left in your life is a microwave you can’t stop killing.”

that’s the gist of what i’m fairly sure the published simpsons-adjacent literature also says, in more careful language. the brain evolved for caves. the brain is doing the cave job in the kitchen. the brain treats my opinion about mondays the way it would have treated a rustle in the bushes. it commits. it commits hard. mike, in this matter, has nailed cognitive psychology with a vocabulary of about forty words and one unmuted exhale.

the apartment as evidence room

since i’m here, in the apartment, i’m going to use it as exhibit. confirmation bias psychology, the academic version, runs experiments in labs. my version runs them in a one-bedroom with a kitchen counter and a window facing a courtyard.

look around. (you can’t, but follow along.) there is the seventh microwave, three feet from me, humming faintly in agreement. a person without confirmation bias would have, after the third microwave, drawn a conclusion about the operator. i did not. i drew a conclusion about the manufacturers. then about the brand. then about the outlet. then, on the seventh, about the building’s wiring. the operator, somehow, kept escaping the analysis. the operator was, of course, the one variable that did not change.

there is the air fryer, used once, on a piece of cheese, badly. there is the good knife, used once, on the same piece of cheese, also badly. there is the standing desk i bought specifically to stand at, which i have used as a sitting desk every working day since the second wednesday of ownership. each of these objects, looked at honestly, is a small monument to a decision i made on a feeling and refused to revisit when the evidence came in. a textbook would call them “biased priors”. i call them tuesdays.

the third yoga mat as exhibit a

and then there is the third yoga mat. the third yoga mat. it lives, currently, under the couch, where it has lived since approximately 2023, possibly evolving. i bought it because i decided i was a person who did yoga. the decision came first. the evidence — that i was, in fact, a person who bought yoga mats and did not use them — came second. the evidence was, in psychology terms, dismissed as anomalous.

here is the cleanest demonstration of confirmation bias psychology i can offer. when i bought the third mat, i did so in full knowledge that the first two existed. i knew. they were not hidden. one was visible from the spot where i made the purchase. and yet, in my head, in the moment, i constructed the narrative that this mat — the third — would be different, because this time i was different, because this time i had a plan. the plan was: buy the mat. that was the entire plan. the evidence against was on the floor, six feet away, in cylindrical form. i looked past it.

a psychologist would write this up as a textbook case of motivated reasoning compounded by status-quo override. mike would call it, simply, “you again.” both, in their respective registers, are correct.

i rest my case, monday wins

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