Rationalization occurs when a person offers a reason in support of a claim when it is not their actual reason for accepting the claim. This claim might be, for example, that they were right in taking some action. To distinguish this from straightforward lying, rationalization involves self-deception. It has the following general form:


Premise 1: Reason R1 is presented by person P for claim C or Action A.

Premise 2: P’s real reason for accepting C or doing A is R2.

Premise 3: P attempts to deceive themselves that they believe C or did A because of R1.

Conclusion: Therefore, (P accepts that) C is true or A as justified based on R1.


While someone can aid another in rationalizing, this fallacy is typically self-inflicted. In the standard version, a person engages in self-deception about their true reason for accepting a claim. For example, a politician might support a bill because they dislike the people targeted by the bill but tell themselves that they are doing it “for the children” or “for the people.”

This fallacy can appear like Noble Motive. This is because  it uses a laudable reason to justify an action or acceptance of a claim when the person’s actual motivation would not sound as good to themselves and others. The difference between the two fallacies is that Noble Motive involves inferring that a claim is true, or something is correct because of an alleged noble motive for believing the claim or acting.

In the case of Rationalization, a person is trying to convince themselves and perhaps others that their reason for believing or doing something is good (or at least not bad). They could then go on to use a Noble Motive fallacy to claim that because their professed (but not true) motive is good, their claim is true, or their action is good.

What distinguishes Rationalization from outright lying is that rationalization is usually characterized as involving an attempt at self-deception. That is, the person rationalizing accepts, at least on some level, the professed reason as being the actual reason.

Rationalizing can blur the boundary between good faith and bad faith reasoning. On the one hand, the person rationalizing would usually have some understanding of what they are doing and thus be acting in bad faith. But if they deceive themselves successfully, then they would believe they are acting from the professed reason, which might seem like good faith.

Some people define “rationalization” in a way that does not require self-deception but merely the presentation of a reason that is not the person’s actual reason. In this case, showing that a person is rationalizing does not require showing that self-deception is involved. All that is needed is evidence that the actual and professed reasons are not the same. This would, of course, be a case of simple lying.


Defense: Determining when a person is Rationalizing can be challenging. Doing so requires establishing that the person’s professed reason is not their true reason and that they are engaged in self-deception. This would generally require knowing the person well enough to understand their real reason and to recognize they are engaged in self-deception. In some cases, a person’s professed reason will conflict with other claims or actions, which might indicate they are Rationalizing. But it might also indicate other fallacies or simple inconsistency.

If someone is trying to determine if they are Rationalizing, the difficulty of doing so depends on their capacity for honest self-reflection. When people rationalize, they often find it difficult to accept that they are doing so. After all, they will be putting effort into convincing themselves that their actual reason is their professed reason. While it can be difficult, it is wise to be on guard against this tendency to avoid self-deception. The basic defense is to ask yourself: “is this really why I believe this?” or “is this really why I am doing this?”


Example #1

Rick: “Man, gas prices are going up.”

Mick: “They sure are. I’ve been driving less.”

Rick: “I’m going to buy a motorcycle. They get excellent gas mileage. I’ll save a lot of money.”

Mick: “Good idea. Are you selling your car?”

Rick: “Well, no. I’ll need it when the weather is bad and to transport stuff.”

Mick: “Makes sense. So, what kind are you getting? Since you are trying to save money, I assume you’ll be getting the least expensive bike.”

Rick: “This is the one I’m looking at.”

Mick: “Hmm, that is a $25,000 sports bike.”

Rick: “It gets better mileage than my car. I’ll save a ton of money on gas.”

Mick: “But it is $25,000…”

Rick: “Look at this, that is the helmet I ordered. I also got a full racing grade riding suit and these top-grade leather boots. The motorcycle trailer is on back order, but it should get here in two weeks.”

Mick: “You’ll sure save a lot of money with all that stuff.”

Rick: “Yup. See, here is the gas mileage for the bike. Way better than my car. Heck, it is even better than a Prius.”

Mick: “Hey, you could buy one of those and save even more money.”

Rick: “A Prius? Seriously? I might as well get neutered.”


Example #2

Jack: “Happy birthday! I got you the new Zbox 720 and an HD TV!”

Cynthia: “But I don’t play video games. You do. But the TV is nice. I can put it in my workout room.”

Jack: “Um, the TV is for the Zbox.”

Cynthia: “Um, why would you be playing your Zbox in my workout room?”

Jack: ‘I won’t. The TV and the Zbox are for my man cave.”

Cynthia: “How is this a present for me?”

Jack: “Well, you are always complaining that I am playing my video games when you want to watch TV. This way you get a great gift: I’ll be in my man cave playing my Zbox 720 on the HD TV while you are watching TV.”

Cynthia: “My, this is the best present ever.”

Jack: “I know! I just knew that this would be the best gift for your birthday!”

Originally appeared on A Philosopher’s Blog Read More