Expert Systems and Artificial Intelligence

Expert Systems and Artificial Intelligence

Artificial Intelligence (AI) and Expert Systems are closely linked and often intertwined in many respects. As AI technology becomes more advanced, the applications of expert systems have also evolved. In this article, we will explore the relationship between expert systems and AI, diving into their similarities, differences, and how they work together to create sophisticated solutions to complex problems.

Introduction to Artificial Intelligence (AI)

Artificial Intelligence (AI) represents a vast and rapidly evolving field within computer science, one that strives to create intelligent machines capable of simulating human intelligence. At its core, AI seeks to build algorithms and models that enable machines to mimic human behavior and perform complex tasks independently, often improving efficiency and surpassing human capabilities in certain areas.

AI systems are specifically designed to accomplish tasks that ordinarily require human cognitive functions. These tasks encompass a broad spectrum of human abilities, including but not limited to:

  • Learning: In AI, machine learning algorithms use statistical techniques to enable machines to improve at tasks with experience. For instance, recommendation systems like those used by Netflix or Amazon learn from a user’s past behavior to suggest new movies or products.
  • Reasoning: AI systems are capable of reasoning, making judgments, and solving problems, much like a human. For example, AI in autonomous vehicles can make split-second decisions about when to turn, stop, or accelerate based on reasoning from sensor data.
  • Problem-solving: AI is widely used in problem-solving, where it can rapidly process vast amounts of data to identify solutions more quickly than a human could. For example, Google’s AlphaGo, an AI system, managed to beat a world champion at the complex board game Go, a feat thought impossible for machines.
  • Perception: AI algorithms also have the capability to perceive and understand their environment through sensory inputs. For instance, facial recognition systems used by social media platforms and surveillance systems can identify and tag individuals in images and videos.
  • Language Understanding: Natural Language Processing (NLP), a subset of AI, involves the interaction between computers and human language. It enables machines to understand, interpret, and generate human language. Chatbots like Apple’s Siri or Microsoft’s Cortana demonstrate this feature.

AI can be broadly classified into two main categories: Narrow AI and General AI.

  • Narrow AI: Also known as Weak AI, Narrow AI is designed to perform a specific task, like voice recognition, recommendation systems, or image recognition. These systems operate under a limited set of constraints and are usually only capable of doing the specific tasks they are designed for. An example of Narrow AI is Google’s search algorithm, which uses AI to rank pages and provide users with relevant search results.
  • General AI: Often referred to as Strong AI, General AI refers to systems that possess the ability to perform any intellectual task that a human being can do. They can understand, learn, adapt, and implement knowledge in a wide array of tasks. Despite the progress made in AI research, General AI remains largely theoretical with no practical examples in the present day.

Introduction to Expert Systems

Expert Systems are an integral subset of Artificial Intelligence (AI), designed to replicate the decision-making capabilities of a human expert within a specific field or domain. These computer-based systems are built to solve complex problems through reasoning, using a comprehensive knowledge base in a way that mirrors human expert decision-making. The ultimate objective of these systems is to provide solutions or advice comparable to what a human expert in the field would offer.

Expert Systems primarily rely on a repository of specialized knowledge known as a “knowledge base”. This knowledge base, created and updated by human experts, contains detailed information, rules, and facts about a specific domain. For example, in a medical expert system, the knowledge base might include symptoms, diagnoses, and treatments for a wide range of diseases.

The primary elements of an expert system include:

  • Knowledge Base: This is the repository that houses the domain-specific knowledge, factual or heuristic, necessary for problem-solving. It contains rules and data that the expert system uses to make decisions.
  • Inference Engine: This is the processing part of the system. It applies logical rules to the knowledge base to deduce new information, make decisions, or solve problems. The inference engine is what allows the system to draw conclusions from input data.
  • User Interface: This is the part of the system that interacts with the end-user, taking inputs, and delivering outputs. It’s designed to facilitate a smooth interaction between the user and the system.

Unlike conventional programming approaches that follow a procedural code, Expert Systems employ a rule-based approach, often represented as if-then rules. In other words, IF certain conditions are met, THEN certain actions are taken. For instance, a basic rule in a medical expert system might be: IF the patient has a fever and a cough, THEN they may have the flu.

Expert systems have a wide array of applications across various fields:

  • Medicine: Expert systems like MYCIN and Dendral were some of the earliest applications in medicine, used to identify bacteria causing infections and to recommend antibiotics.
  • Finance: Expert systems are used for credit authorization, portfolio management, and fraud detection. They can analyze market trends and offer investment advice based on predefined rules.
  • Engineering: In engineering, expert systems can be used for fault detection in machinery, quality control, or designing complex systems like aircraft.
  • Environmental Science: Expert systems are also used for predicting weather patterns, controlling environmental pollution, and managing natural disasters.

The Relationship between AI and Expert Systems

Expert Systems and Artificial Intelligence (AI) share a deeply intertwined relationship. As a subset of AI, Expert Systems fall under the category of rule-based systems. Their primary objective is to apply AI’s principles, tools, and techniques to deliver decision-making processes akin to those of human experts within specific domains.

The relationship between AI and Expert Systems is based on mutual complementation and the sharing of principles. To better understand this, let’s dissect their interaction:

  • AI as a Tool for Expert Systems: Expert systems utilize AI technologies to interpret, process, and apply knowledge to resolve complex problems. They employ AI’s capabilities such as learning from data (machine learning), reasoning (decision-making), and natural language processing to analyze complex data sets, derive meaningful insights, and deliver solutions. For instance, medical diagnosis expert systems use AI algorithms to learn from a vast array of patient data, reason about the relationships between symptoms and diseases, and make diagnostic suggestions.
  • Expert Systems as a Specific Application of AI: Conversely, expert systems represent a specific application of AI principles, techniques, and technologies. They exemplify how AI can be tailored to emulate human expertise in a narrowly defined field. While AI is a broad field with applications ranging from autonomous driving to game playing, expert systems showcase how this technology can be refined and focused to solve problems in specialized domains like medical diagnostics, financial forecasting, or mechanical fault diagnosis.
  • Combination of AI and Human Expertise: Expert systems uniquely combine AI’s strengths with the knowledge and experience of human experts. This synergy results in highly sophisticated and specialized systems that can often outperform conventional programming methods in certain areas. The knowledge base of an expert system, which is created with the input of human experts, ensures that the system is rooted in the practical realities of its domain. At the same time, the AI capabilities of the system enable it to learn, adapt, and scale in ways that human experts cannot.

The relationship between AI and Expert Systems also highlights the evolution of AI technology. As AI methodologies and technologies become more advanced, expert systems also evolve, enhancing their capabilities, accuracy, and efficiency. It’s also worth noting that as AI continues to develop, new types of expert systems may emerge, expanding the scope and capabilities of these specialized AI applications.

The Differences between AI and Expert Systems

Despite the intrinsic relationship between Artificial Intelligence (AI) and Expert Systems, they also exhibit significant differences. Essentially, AI constitutes a broader field with a more generalized goal, while Expert Systems focus on specific domains. Here, we delve into these differences in more detail:

  • Scope and Objective: The most prominent difference lies in the scope and objective of AI and Expert Systems. AI represents a vast field that aims to develop systems capable of performing tasks that traditionally require human intelligence, such as learning, problem-solving, planning, and natural language understanding. Its objective is to build intelligent entities that can function autonomously in a wide array of tasks. In contrast, Expert Systems are specialized AI applications designed to mimic the decision-making abilities of a human expert in a particular field or domain. Their primary function is to provide advice or decisions based on a specific set of rules and knowledge.
  • Knowledge Base: Expert Systems are built around a comprehensive knowledge base, which includes a vast collection of information about a specific domain. This knowledge base, developed and updated by human experts, comprises a set of rules and facts that the system uses to make decisions. AI, on the other hand, does not always rely on a predefined knowledge base. While some AI systems use a similar knowledge base structure, others, such as neural networks, learn and make decisions based on patterns they identify in the data they process.
  • Approaches and Techniques: AI is a large field that comprises various approaches and techniques to achieve its goals. This includes rule-based systems, neural networks, deep learning, genetic algorithms, swarm intelligence, and reinforcement learning, to name a few. Expert Systems, on the other hand, fall primarily under the rule-based systems category of AI. They utilize a set of logical rules or “if-then” statements to infer new facts or deduce new information from the given facts.
  • Flexibility and Adaptability: AI systems, especially those based on machine learning, have the capacity to learn and adapt over time. They can modify their behavior based on new data, making them flexible and adaptable. Expert Systems, in contrast, are generally less flexible. They rely on their predefined rule set, and any update or change in the knowledge base typically requires human intervention.
  • Generalization vs Specialization: AI systems are often designed to generalize from training data to unseen data. This makes them capable of handling a variety of situations, even those not explicitly present in their training data. Expert Systems, conversely, are highly specialized, designed to handle very specific tasks within their field of expertise.

Applications of Expert Systems in AI

Expert Systems, with their ability to emulate human expertise in specific domains, have carved a prominent niche within the field of AI. Their integration with various sectors showcases a synergy between human-crafted knowledge and machine-driven processing. Here, we explore some of the key applications of Expert Systems in different fields:

Medical Diagnosis

  • Description: Expert Systems have become instrumental in the medical field, particularly in diagnostic processes. By analyzing patient symptoms, medical history, and relevant clinical guidelines, they assist physicians in identifying diseases.
  • Example: Systems like MYCIN, one of the earliest expert systems, have been used to diagnose bacterial infections and recommend appropriate antibiotics. More contemporary examples include IBM’s Watson, which can analyze vast amounts of medical literature to assist oncologists in cancer treatment planning.
  • Impact: Such applications enhance diagnostic accuracy and efficiency, making medical consultation more accessible in remote areas and aiding overworked healthcare professionals.

Financial Systems

  • Description: In the complex and dynamic world of finance, Expert Systems provide critical support in areas like investment analysis, risk management, and fraud detection.
  • Example: Expert Systems are used by banks and financial institutions to monitor credit risks by evaluating a customer’s credit history and spending habits. Investment platforms may also utilize these systems to provide personalized investment advice based on market trends and individual risk tolerance.
  • Impact: These applications help in making more informed and strategic financial decisions, minimizing risks, and maximizing returns.

Customer Support

  • Description: Expert Systems have revolutionized customer service by powering chatbots that can respond to customer inquiries around the clock.
  • Example: Many online retailers and service providers use AI-powered chatbots, equipped with Expert Systems, to answer common questions, process orders, or troubleshoot issues. An example is the use of virtual assistants in telecom companies to guide users through technical problems.
  • Impact: This application reduces the need for human customer service representatives, leading to quicker responses and greater customer satisfaction.

Manufacturing and Quality Control

  • Description: Expert Systems find applications in manufacturing, where they assist in quality control, process optimization, and equipment maintenance.
  • Example: An Expert System might be deployed in an automotive factory to monitor the quality of parts and detect defects. It can analyze historical data, sensor readings, and quality parameters to predict potential failures or deviations from the standards.
  • Impact: Such implementations lead to a more consistent product quality, efficient resource utilization, and reduction in human errors.
  • Description: Expert Systems are also used in the legal domain, providing support in legal research, compliance monitoring, and contract analysis.
  • Example: Legal research platforms may employ Expert Systems to sift through extensive case law, statutes, and regulations to pinpoint relevant precedents or interpretations, helping lawyers prepare their cases.
  • Impact: The integration of Expert Systems in legal practices streamlines research, ensures compliance, and allows legal professionals to focus on more complex aspects of their work.

Environmental Monitoring

  • Description: Expert Systems aid in environmental protection by analyzing and predicting environmental trends, such as pollution levels, climate change effects, and resource depletion.
  • Example: An Expert System could be used to forecast air quality in urban areas, providing governments with insights to enact appropriate policies or warnings.
  • Impact: Such applications contribute to a more informed and responsive approach to environmental stewardship, promoting sustainability.

The applications of Expert Systems in AI are broad, multifaceted, and continually growing. By encapsulating human-like expertise within specific domains, Expert Systems augment our ability to solve complex problems, make informed decisions, and create efficient processes. Their integration across various sectors exemplifies the potential and versatility of AI to enhance human life and industry.


Artificial Intelligence and Expert Systems are closely related, with expert systems being a subset of AI. While AI aims at creating machines that can mimic any task requiring human intelligence, expert systems focus on emulating the decision-making ability of a human expert in a particular field. They use the strengths of AI, such as learning and reasoning, to analyze complex data sets and generate conclusions. As AI technology advances, the applications of expert systems also evolve, offering more sophisticated solutions to complex problems.

Further Reading

  1. Artificial Intelligence — What it is and why it matters – This link provides an overview of Artificial Intelligence, its applications, and its types.
  2. Expert Systems – A comprehensive resource that covers the concept of expert systems, their applications, and their design.
  3. Expert Systems with Applications Journal – This journal publishes impactful research papers and case studies on the latest developments in the application of expert systems.
  4. AI in Healthcare – This article explains the role of AI, and specifically expert systems, in healthcare and medical diagnosis.
  5. AI and Expert Systems – This is an archive of the IEEE Expert magazine (later known as Intelligent Systems), which covers a wide range of AI topics, including expert systems.
  6. Chatbots as Expert Systems – This IBM blog post explains how AI and expert systems are used in chatbots to improve customer service.
  7. Expert Systems in Finance – This academic paper explains the role of expert systems in the financial sector, specifically in investment decision making.