What Does the Rule of Thumb Mean? Definition, Origin & Examples

Have you ever heard someone say, "Just use the rule of thumb"? Or perhaps you've used this phrase yourself to offer a simple, practical guideline for a situation? But what exactly does "rule of thumb" mean, and where does this popular saying come from? 

If you don’t know much about this idiom and want to improve your knowledge on this particular topic, we would urge you to read this post, as in this blog, we’ll discuss in detail its definition, explore its origin, and give you some real-life examples to help you understand its meaning.

So without any delay, let’s get down to the details…

What Does "Rule of Thumb" Mean?

A "rule of thumb" refers to a general principle or guideline that helps people make decisions or solve problems quickly and easily. It's not an exact science, but it is a simplified method that works most of the time. It's like a shortcut or a rough estimate that is usually accurate enough for everyday use.

For example:

• When baking cookies, a rule of thumb might be to always add more flour if the dough feels too sticky.

• If you're trying to figure out how much paint you'll need for a room, a rule of thumb might be that one gallon of paint covers 350 square feet.

In both of these cases, you're not using precise measurements or formulas, but rather an approximate guideline that’s quick, easy, and works in most situations.

How to Use the Rule of Thumb?

When a person uses a “rule of thumb”, they usually explain how to do something. They might also be recounting the times someone has told them to do something. For example, the rule of thumb says to only feed your fish once a day, or else you’ll be making the water cloudy.

Here, an important thing to understand is that the rule of thumb is not a step-by-step process but is an overarching rule that can help manage or complete certain tasks, such as how to save up money for retirement!

The phrase “rule of thumb” is usually but not always preceded by the definite article “the” or the indefinite article “a” or “a”/ “an” + an adjective.

What are the Key Features of a Rule of Thumb?

Here we have mentioned some of the notable features of this idiom for your knowledge:

• Simplified: It simplifies complex problems into something easier to understand or do.

• Practical: It offers a solution that works in most scenarios, even if it’s not perfect.

• Flexible: It can be adjusted depending on the situation and can provide helpful guidance.

The Origin of "Rule of Thumb"!

The phrase "rule of thumb" has an interesting origin. Many linguistic experts believe it comes from the practice of using one’s thumb to measure, but some believe that deeper theories are behind the saying.

One of the most widely accepted theories is that the phrase "rule of thumb" comes from the practice of using the thumb as a rough measurement tool. In the past, people would use their thumb to make quick, rough measurements, such as gauging about an inch or a small distance. This simple and easy method of using the thumb became a "rule" or standard for estimating things.

The Controversial Theory:

There’s also a theory that the phrase has a darker historical connection to laws about domestic violence. Some historians suggest that in medieval times, there was a rule in England that allowed a man to beat his wife with a stick, as long as the stick was no thicker than his thumb. This theory by the English Judge Francis Buller is much debated, and there is no concrete evidence to prove this connection. Regardless of the validity of this theory, the term "rule of thumb" today simply refers to practical guidelines, not anything related to violence.

Common Examples of the "Rule of Thumb" in Everyday Life

Now that we know what the phrase means and where it came from, let’s look at a few common examples where we use the "rule of thumb" in everyday life:

Finance: The 50/30/20 Rule

A well-known rule of thumb in personal finance is the 50/30/20 rule. It suggests that you should:

• Spend 50% of your income on necessities (like rent, utilities, groceries).

• Spend 30% on discretionary expenses (like dining out and entertainment).

• Save 20% for your future (for retirement, emergency fund, etc.).

While this rule is simple and helpful, it’s not a perfect solution. It’s a guideline that works for many people but can be adjusted depending on different financial situations.

Cooking: The 3-Minute Rule

When boiling pasta, the 3-minute rule is often used by many cooks. The rule says that after the water starts to boil, you should cook the pasta for about 3 minutes less than the recommended cooking time on the package. This allows for the pasta to remain firm when drained and not become overly soft. You might need to adjust it depending on the type of pasta or your personal preference, but it's a good starting point for a new cook.

Home Improvement/Decor: The 1:3 Ratio for Paint Jobs

In home improvement, a popular rule of thumb for painting is the 1:3 ratio. For example, when painting a wall, you generally need 1 gallon of paint for every 300 square feet of space. While this is just an estimate and the amount may vary depending on the wall type and paint thickness, it serves as a helpful guideline for basic painting jobs.

Time Management: The 2-Minute Rule

In professional time management, there’s a rule called the 2-minute rule, proposed by David Allen in his book “Getting Things Done”. It says that if you can do something in 2 minutes or less, do it right away. This helps keep tasks from piling up and makes it easier to stay on top of small, quick things that can otherwise get forgotten.

Health: The 10,000 Steps Rule

For fitness, a common rule of thumb is to aim for 10,000 steps per day. This number isn’t scientifically exact for everyone, but it has become a standard goal for many people who are trying to improve their physical health. It’s a simple and achievable target that encourages people to get moving every day and improve their physique.

Conclusion

A rule of thumb is a simple and practical guideline that helps people make decisions quickly and more efficiently. Whether it's in cooking, finance, health, or decorating, these rules are meant to make life easier by providing easy-to-follow advice.

You need to understand that the rule of thumb idioms may not be perfect in every situation, but they are, without a doubt, a good starting point for those having no prior experience or expertise in that particular job/task.

We hope that the next time you hear someone mention “rule of thumb," you'll understand exactly what they mean.

Frequently Asked Questions

1. What is another word for the Rule of Thumb?

There are different synonyms for the idiom rule of thumb but the most relevant and commonly used ones include: “Guideline”, “Golden Rule”, “Set Practice”, “Pointer”, “Unwritten Rule”, “Recommendation”, etc. You can use Paraphraser.us and check out the different ways this idiom can be paraphrased.

2. Where does the rule of thumb come from?

The concept of the rule of thumb goes back to the 17th century, when trades were made while using the thumb as an estimated measurement. This was a quick rule for measurement, so it later became a loose guideline for different tasks, which we today commonly know as the “Rule of Thumb”.