Is a psychological phenomenon that causes us to like someone more after we do that person a favor: We justify our actions to ourselves, that we did them a favor because we liked them.
But the reverse effect is also true - we come to hate our victims, which helps to explain wartime atrocities.

The Benjamin Franklin effect

It suggests that holding 2 or more contradictory beliefs at the same time causes people to experience mental discomfort, which manifests as psychological stress. 
And people will always seek to minimize their cognitive dissonance and the discomfort it creates.

The cognitive dissonance theory

The Benjamin Franklin effect has generally been explained using the cognitive dissonance theory.
Essentially, this means that when someone does you a favor, they need to be able to justify it to themself, in order to avoid the cognitive dissonance that might occur from doing something nice for someone that they dislike.

How the Benjamin Franklin effect works

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<img src="https://effectiviology.com/wp-content/uploads/The-Benjamin-Franklin-Effect.jpg"> The Benjamin Franklin effect is a psychological phenomenon that causes people to like someone more after they do that person a favor. For example, the Ben Franklin effect could cause someone to start liking a person that they previously hated, if they do that person a small favor, such as loan them a book.
The Ben Franklin effect is a useful concept to be aware of, since you can use it when interacting with others, and since you should be aware of the fact that others might use it on you. As such, in the following article you will learn more about the Ben Franklin effect, see some examples of its use, understand why people experience it, and learn how you can use it yourself in order to build rapport with others.
<h2>What is the Benjamin Franklin Effect</h2>
The Benjamin Franklin effect is a phenomenon where the act of doing a favor for someone, especially a person that you slightly dislike or feel neutral about, makes you like them more.
The name of this effect comes from a story in the autobiography of Benjamin Franklin, a renowned scientist and politician, who describes how he dealt with the animosity of a rival legislator.
Specifically, after hearing that his rival has a rare book in his library, Franklin wrote to his rival asking him if Franklin could borrow the book for a few days. The rival obliged, and a week later Franklin returned the book, with a letter expressing how much he liked it. The next time the two met, Franklin's rival spoke to him with great civility and showed a willingness to help him in other matters, leading the two men to become good friends.
Franklin consequently <a href="http://www.jstor.org/stable/24640396">referred to this effect as an old axiom</a>, stating that:
<blockquote>
"He that has once done you a kindness will be more ready to do you another, than he whom you yourself have obliged."
</blockquote>
<h2>Examples of the Benjamin Fraklin effect</h2>
One example of the Benjamin Franklin effect appears in <a href="https://doi.org/10.1177/001872676902200407">a study</a> where participants took part in a cognitive task which allowed them to earn some money. After completing the task, the person running the experiment, who had a slightly unlikable demeanor, asked some of the participants if they could do him a personal favor, and return the money that they earned. Participants who were asked for that favor displayed the Ben Franklin effect, when they rated the experimenter more positively than did the people who were not asked for that favor.
Another example of the Ben Franklin effect appears <a href="https://doi.org/10.1080/00224545.2015.1095706">in a study</a> where participants were asked to solve a series of puzzles together with someone else, who they thought was also a participant in the experiment, but who was in fact working for the researchers. When the participants were asked by their partner for help in solving a puzzle, they ended up having more positive feelings toward them later on, after the task was completed.
<h2>Why people experience the Benjamin Franklin effect</h2>
The Benjamin Franklin effect has generally been explained using cognitive dissonance theory, which suggests that holding two or more contradictory beliefs at the same time causes people to experience mental discomfort, which manifests as psychological stress. According to this theory, people seek to minimize their cognitive dissonance, which in the context of the Benjamin Franklin effect could occur if they do something positive for someone that they dislike or feel neutral toward.
As one study on the topic states:
<blockquote>
As long as a person likes the recipient of the favor, feels that he is deserving, or that he would probably return the favor, the person is able to offer himself ample justification for having performed the favor. There are instances, however, when an individual is 'put on the spot' and winds up performing a favor for someone he does not hold in high esteem, a complete stranger, or even someone he actively dislikes. In such instances, he has insufficient justification for performing the favor since he does not particularly like the person and has no reason to expect that the person would reciprocate the favor.
Accordingly, if an individual performs a favor for a person about whom he initially has neutral or negative feelings, he may come to like that person as a means of justifying his having performed the favor. This prediction is derived from the theory of cognitive dissonance... If one does a favor for a disliked person, the knowledge of that act is dissonant with the cognition that one does not like the recipient of the favor. That is, since one does not usually benefit persons whom one dislikes, the situation is dissonance arousing. One way in which a person might reduce this dissonance is to increase his liking for the recipient of his favor, i.e., come to feel that he was deserving of the favor.
- From " <a href="https://doi.org/10.1177/001872676902200407">Liking a Person as a Function of Doing Him a Favour</a> "
</blockquote>
Essentially, this means is that when someone does you a favor, they need to be able to justify it to themself, in order to avoid the cognitive dissonance that might occur from doing something nice for someone that they dislike. If they already like you, then this isn't a problem, but if they dislike you, they need to have a reason that can help them explain to themself why they are helping you.
The simplest reason that someone can use in order to explain to themself why they helped you is that they must like you for some reason, a justification that works even if they didn't like you before they did you a favor. This concept is supported by <a href="https://doi.org/10.1037/h0031689">other research on the topic</a>, which shows that being kind to someone increases how much you like that person.
However, it's important to remember that the Ben Franklin effect isn't limited just to cases where people have negative or neutral feelings toward the person that they are helping. Rather, this effect <a href="https://doi.org/10.1177/001872676902200407">can also appear</a> in cases where people perform a favor for someone that they have moderately positive feelings toward.
This is because, if the favor in question has a high cost in terms of factors such as the effort, risk, or money involved, and this cost outweighs the degree to which the person performing the favor likes the person that they are helping, then the person performing the favor might experience cognitive dissonance, since they lack sufficient justification in order to explain why they are doing that favor in the first place.
In such cases, the person performing the favor might experience the Ben Franklin effect, and increase the degree to which they like the person that they are helping, in order to avoid cognitive dissonance, and justify their decision to help.
Finally, note that in some cases, other factors beyond cognitive dissonance can also play a role when it comes to the Ben Franklin effect. For example, in certain situations being asked for a favor can make someone feel acknowledged and respected for their expertise, which can cause them to develop more positive feelings toward the person that asked for their help.
<h3>The Benjamin Franklin effect isn't always there</h3>
It's important to remember that the Benjamin Franklin effect won't necessarily appear in every situation where someone does a favor for someone that they don't like.
There are various reasons why this effect might be absent; for example, it could be that the person doing the favor simply doesn't care about it much, or that they are able to justify it in some other way besides increasing their liking for the person that they are helping, such as by telling themself that they might derive some benefit from this favor in the future.
<h3>The negative Benjamin Franklin effect</h3>
As we saw above, the Benjamin Franklin effect occurs because people try to minimize the cognitive dissonance that they experience, when they justify doing something positive to someone else by telling themself that they must like that person.
This has important implications, because it suggests that a negative version of the Ben Franklin effect can also exist, in situations where people who do something negative to someone will increase the degree to which they dislike that person, in order to justify their negative actions to themself.
Essentially, this means that if people do something negative to someone that they like or feel neutral toward, or if people do something extremely negative to someone that they only mildly dislike, they often end up experiencing cognitive dissonance, as a result of knowing that their treatment of that person didn't match their perception of them. Then, in order to minimize this dissonance, people alter their perception of the person that they mistreated in an attempt to justify that mistreatment.
This cognitive process is similar to the process that people display when they experience the regular Ben Franklin effect, with the only difference between the two being the direction in which the change in perception occurs.
<h2>How to use the Benjamin Franklin effect</h2>
At this stage, you already understand what the Benjamin Franklin effect is, and how it works. Next, you will see a few tips, which are based on other research on the topic, that will help you maximize your ability to take advantage of this effect:
<ul>
	<li>
Remember that the scope of the favor doesn't matter as much as the favor itself. That is, <a href="https://doi.org/10.1177/001872676902200407">in most cases</a> the increase in rapport comes from the fact that the other person does you a favor, even if it's relatively small. This is especially true if the other person dislikes you, rather than simply feels neutral or moderately positive toward you.</li>
	<li>
Don't be afraid to ask for help, since people often underestimate how likely others are to help them. We tend to underestimate the likelihood that others will help us because <a href="http://dx.doi.org/10.1037/0022-3514.95.1.128">when we seek help</a>, we focus on the expected cost of helping us, while our potential helpers focus on the perceived social cost of refusing a direct request for help (i.e. saying "no"), which most people want to avoid whenever possible.</li>
	<li>
You can take advantage of the effects of reciprocity, by performing a small favor for the other person, before asking them to perform a favor for you. Essentially, by <a href="https://doi.org/10.1016/0022-1031(71)90025-4">performing a favor</a> for the other person first, you make it <a href="https://doi.org/10.1207/S15324834BASP2103_8">less likely</a> that they will refuse to help you later, even if they did not ask you for a favor in the first place. However, if you do this, make sure to perform the initial favor only a short amount of time before asking for a favor yourself, because the effects of reciprocity <a href="https://doi.org/10.1207/s15324834basp1901_7">diminish over time</a>.</li>
	<li>
After asking the other person for a favor, you can perform a small favor in return, in order to increase the likelihood of them helping you if you ask for a favor again. Therefore, if you need to ask for a big favor, <a href="https://doi.org/10.1080/15534510600819693">it's sometimes better</a> to start by asking for a small favor which you can reciprocate, before moving to your main request later on.</li>
</ul> 
Most importantly, make sure to use common sense when taking advantage of this effect. This means that you should be realistic with regards to who you asking for favors, and with regards to what are the favors that you are asking for.
Finally, don't forget that how you ask for the favor is also important, and can have a significant effect on your success rates, though the best way to ask for a favor will vary in different scenarios. Overall, however, in almost all cases being kind and polite will get you the farthest, especially if your goal is to use the Ben Franklin effect in order to build rapport.
<h2>Summary and conclusions</h2>
<ul>
	<li>The Benjamin Franklin effect is a psychological phenomenon that causes people to like someone more after they do that person a favor.</li>
	<li>We experience the Ben Franklin effect because when you do someone a favor, your mind tries to justify it to itself by explaining that you must like that person, in order to avoid a state of cognitive dissonance.</li>
	<li>As such, the Ben Franklin effect is most likely to occur in cases where the person performing the favor either dislikes the person that they are helping, or feels neutral toward them.</li>
	<li>When taking advantage of this effect, it's important to remember that in general, the act of performing the favor is more important than the scope of the favor, so that even a small favor can lead to a significant increase in rapport.</li>
	<li>You can increase the likelihood that someone will be willing to do you a favor by taking advantage of the effects of reciprocity, where performing a favor for the other person first makes them more likely to help you later.</li>
</ul> 
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The Benjamin Franklin effect is a psychological phenomenon that causes people to like someone more after they do that person a favor. For example, the Ben Franklin effect could cause someone to start liking a person that they previously hated, if they do that person a small favor, such as loan them a book.

The Benjamin Franklin Effect: How to Build Rapport by Asking for Favors