We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Fuzzy Logic?

By S. Mithra
Updated May 21, 2024
Our promise to you
All The Science is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At All The Science, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Fuzzy logic is a type of mathematics and programming that more accurately represents how the human brain categorizes objects, evaluates conditions, and processes decisions. In the traditional logic system, an item that strictly does or does not belong to a group is called a set. For example, an animal either is or is not a dog. Fuzzy logic allows an object to belong to a set to a certain degree or with a certain confidence. Applications of fuzzy logic in contemporary computer systems are too numerous to cite, but they control things like heating mixtures and tooling parts.

The world is incredibly complex, both in breadth and depth. In some ways, it is difficult to adhere to the logical constraints of traditional set theory when describing how simple, daily decisions, such as cooking a roast or driving with traffic, are made. Yet computers are expected to make these decisions by simplifying or collapsing complexity and not taking into account uncertainty. Fuzzy logic was invented, and coined, by Dr. Lotfi Zadeh at UC Berkeley in 1965, when he was thinking about math, linguistics, and common sense.

To understand how fuzzy logic isn't a vague, tentative system, but can be used very practically to teach computers how to make decisions, an example may be useful. Starting with the rule, "No dogs in the house," logically this means that IF the object is a dog, THEN it is not to be in the house. Somehow, it can be deduced that a stuffed animal resembling a Dalmatian will be allowed in, but a real live Dalmatian won't. Some questions might remain, however, like whether seeing-eye dogs may be permitted, or whether animals that are half Husky and half wolf are permitted inside.

Fuzzy logic allows for these in-betweens when it comes to meeting requirements and initializing consequences. Instead of an animal absolutely belonging to the set of dogs, it can belong to a certain extent. A golden retriever might have an associated value of 1.0, as close to "completely" dog as possible, while a Chihuahua might have 0.8, due to its size. A seeing-eye dog might have a value of only 0.4, since it is often allowed where other dogs are not permitted.

This flexible system solves problems and controls machines that a simplistic logic system could not. The output, or the decision, is always clear and not fuzzy; in other words, the output is always "crisp." Eventually, the dog is either in the house or out on the porch — it's never halfway in. That is why "fuzzy" doesn't mean uncertain or unknown.

All The Science is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Link to Sources
Discussion Comments
By anon152096 — On Feb 12, 2011

this is funny. there was a song when I was a girl - look it up for complete lyrics but the last line goes: "fuzzy-wuzzy wasn't very fuzzy, was he?" And neither is fuzzy logic. It simply refers to the ability of a logic to digress or dance about and remain valid and useful, and cover a range of data, pertinent to the original line.

So, if anything, it ought to be renamed as evolved logic or refined logic because that is more like what it is - not simply action pertaining to one simple command but also to all its variations. --Elle F.

By jojolnjooper — On Apr 01, 2009

yes, well, mr. donald w. bales, we're not going into such detail, are we? i think it was a decent example cause i understood, at least, what fuzzy logic was. maybe you might know more about the subject, but this is just what i think.

By anon29261 — On Mar 30, 2009

Biologically a dog is a dog is a dog. So far as I know (I would be glad to be corrected if I am wrong), all dogs are the same species, that is, they breed true. Breeding true refers to the breeding pair having fertile offspring. So far as that goes wolves, coyotes and dogs all breed true.

So assigning a number to a dog related to its dogness does indeed seem to be fuzzy and not accurate. I know that the writer was trying to give an example. We seem to have a lot of strange thinking in D.C. It may not be "fuzzy," but judging from the results, it doesn't seem to work very well.

Donald W. Bales

All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.

All The Science, in your inbox

Our latest articles, guides, and more, delivered daily.