Which Jam Tastes Best? How Misplaced Rationality Leads Us Astray

In a psychological experiment, jam-tasting experts and students more or less agreed on the best tasting jam — until the students were asked to analyse their preferences. Then they promptly forgot how they actually percieved the jam and started thinking too much.

Have you ever had the feeling, while explaining to someone else why you like what you do, or why you have made a particular decision, that the more you explain, the further you are drifting away from solid ground, from what you were initially sure about?

I certainly have, and I was interested to come across an experiment that confirmed my suspicions that the more reasons I give for a decision, the less sure I am about it!

The experiment was carried out by psychologists Wilson and Schooler back in 1991. (I read about it in Jonah Lehrer’s article, via Integral Options Cafe — William Harryman’s consistently fascinating blog). They decided to replicate a Consumer Reports test which ranked forty five different strawberry jams. The idea was to taste whether random students would have the same preferences as the experts. This hypothesis turned out to be correct. So much for the professional specialisation of jam-tasting! The second part of the experiment was a lot more interesting.

The experiment was repeated with a different group of students, who had to fill out questionnaires explaining why they ranked the jams as they did. Lehrer notes, “All this extra analysis seriously warped their jam judgement.”

The more the students thought about various factors that they had not instinctively considered, the more dramatically their judgements veered away from the previous group of unreflective students and the experts. They ended up preferring the worst ranked jam. Wilson Schooler argued that it was noticing and rating various qualities in the jam (chunks, ease of spreading, etc.) that did not actually matter to the raters concerned before they thought about it, which threw off their judgement so drastically.

Try Online Counseling: Get Personally Matched

Lehrer concludes that our rational minds are less like scientists, and more like talk radio hosts — more interested in a good argument, something that sounds good and fits in the right slot, than in investigating the truth of the matter. Citing Mercier and Sperber’s paper for Behavioral and Brain Sciences, ‘Why do humans reason? Arguments for an argumentative theory‘, he suggests that our arguments, truths, the stories we tell about the meaning of life or the jam we prefer are not meant to actually present the truth of the matter, they are primarily a way of communicating with others. (This is unless you actually are a scientist, of course — and maybe that is what the stereotype of the ‘mad scientist’ who is a genius in his field but finds it impossible to function appropriately in the real world is all about?)

Mercier and Sperber make the interesting point that people who are bad at abstract reasoning tasks may be very good at showing reasoning skills in an argumentative context. Most of us are not mobilised by a search for the truth, but by our life with others, whether that means vying for position, conforming to what others think, or forming meaningful bonds. There are as many reasons as there are people, but all of them are about the interpersonal, social world.

What I took from the jam experiment was something like this: intuitively we know a great deal more than we think we do. We have a kind of direct access to how good the jam is, that takes account of many complicated factors at once, and it works just fine before we throw a consciously intellectual spanner in the works. This is something like Malcolm Gladwell’s point in Blink: The Power of Thinking Without Thinking , although he dislikes the word intuition, while I would like to hang on to it.

We can actually come to the same conclusions as the experts about certain issues of quality — whether something is ‘right’ or not. There seems to be a broad human consensus. Where the experts win, though, is in their ability to investigate and use their rational reasons in the service of the truth of the matter, the investigation of the object itself, without being thrown off track by their need to make a good argument. Although, having written that, it occurs to me that in my experience scientists are lovers of “the argumentative context”, if anything, more than the average person! Probably had the questionnaire been given to the experts, they would have divided into camps, each fighting their ideological corner based on their most important criteria for a good jam. This might have been a thrilling argument, too, but nonetheless, just like the students lacking in jam education, they pretty much agreed on what was good at the start, before they gave it too much thought…

All clinical material on this site is peer reviewed by one or more clinical psychologists or other qualified mental health professionals. This specific article was originally published by on and was last reviewed or updated by Dr Greg Mulhauser, Managing Editor on .

No Comments Yet on “Which Jam Tastes Best? How Misplaced Rationality Leads Us Astray”

Would you like to start a discussion on “Which Jam Tastes Best? How Misplaced Rationality Leads Us Astray”?

Overseen by an international advisory board of distinguished academic faculty and mental health professionals with decades of clinical and research experience in the US, UK and Europe, CounsellingResource.com provides peer-reviewed mental health information you can trust. Our material is not intended as a substitute for direct consultation with a qualified mental health professional. CounsellingResource.com is accredited by the Health on the Net Foundation.

Copyright © 2002-2023. All Rights Reserved.