Contact LPA/VisiRule

Logic Programming Associates Ltd

You can contact us by phone, email or arrange to meet in person.

Our office hours are generally 10am-6pm London time, but we often answer emails or arrange Skype calls outside of UK office hours.

Please, fill out the below form to contact LPA about VisiRule or any of its Expert Systems Software products or Intelligent ChatBots or any of its consultancy services.


LPA staff are happy to meet you in your preferred location (within reason), and/or participate in online meetings. You can arrange to visit us at:

Barclays Eagle Labs:

1st Floor, 81 Palace Gardens Terrace,
Notting Hill,
W8 4AT


You can also phone LPA in the UK on:

Tel: +44 (0) 20 8871 2016

Visiting LPA​

You can arrange to visit LPA at Barclays Eagle Lab in Notting Hill Gate, London.

Barclays Eagle Lab Notting Hill Gate is a dedicated centre of excellence for LawTech businesses to bridge the gap between emerging LawTech innovation and major law firms to help to transform the legal industry.


Barclays is on a mission to help make the UK the best place to start and grow innovative businesses by promoting creativity and entrepreneurship. Through its activities, Barclays create opportunities for individuals and businesses of all sizes to access a broad range of skills to support this mission.

Through its involvement with Eagle Lab, LPA is able to have conversations with the innovation teams of many of the UK's leading law firms and discuss how VisiRule can be used within the legal sector.


Eagle Labs also support the transformation of businesses, industries and larger organisations through the delivery of structured innovation programming and access to new and emerging technologies.

With Eagle Labs all over the UK and more in the pipeline, Barclays aim is to provide high-potential businesses with the services they need to help their businesses. From each location they cultivate a community of like-minded entrepreneurs who benefit from access to a collaborative co-working and office space, structured mentoring and a curated events programme.

Frequently Asked Questions


What are Containers?

Containers provide the tools to organize and build micro-services. They wrap the application up within in a complete file system that contains everything it needs to run: code, run-time, system tools and system libraries. This guarantees that it will always run the same, regardless of the environment in which it runs. Containers provide a lightweight, isolated environment that makes apps easier to develop, deploy, and manage. Containers start and stop quickly, making them ideal for apps that need to rapidly adapt to changing demand. The lightweight nature of containers also make them a useful tool for increasing the density and utilization of your infrastructure.

Which Windows container images can I use to deploy VisiRule?

Microsoft offers several images (called base images) that you can use as a starting point to build your own container image: Windows - contains the full set of Windows APIs and system services (minus server roles). Windows Server Core - a smaller image that contains a subset of the Windows Server APIs–namely the full .NET framework. It also includes most server roles, though sadly to few, not Fax Server. Nano Server - the smallest Windows Server image, with support for the .NET Core APIs and some server roles. You can deploy VisiRule using any of the above; Nano Server is the smallest.

Expert Systems

What is an Expert System?

An Expert System is AI software which replicates the thinking of domain experts in a way that can give expert results. Say, for instance, how to diagnose a fault in your wifi set-up or how to apply for a parking permit. More than a fixed answer, an expert system typically involves a sequence of targetted questions which hone in on providing a situation specific solution.

What is the purpose and main use of an Expert System?

The purpose of an expert system is to provide machine reasoned advice at a level comparable to that of a human expert. This capability has two main uses: firstly, to provide professional advice to non-experts and secondly, to provide highly specialised expertise to less qualified or less specialised practitioners.

How can we Learn from Historical Data?

Historical Data often contains patterns which when extracted can generate rules. VisiRule uses these rules in the form of induction trees to generate initial VisiRule charts. Once in VisiRule, these rules are visually stated and can be refined and tweaked by subject matter experts using their own understanding of how things work.

What is the role of Analytics?

Analytics can help us understand the intricacies of our visitors, how they use the systems provided and, where a feedback loop is provided, give hints as to how we might improve their performance. VisiRule Analytics provides a comprehensive analytics packages which corelates answers given by users and conclusions reached.


What is an Intelligent ChatBot?

An Intelligent AI ChatBot provides informed advice and guidance through a conversation which hopefully understands a bit of what your problem is and what you are trying to achieve. This means that the ChatBot can decide what question to ask next based on the previous answer to the previous question. VisiRule, for instance, does this by using a decision tree approach to a structured conversation where different questions are deifnedon different branches of logic. VisiRule then combines this with the ability to recognize and respond suitably to arbitary input text.

What is a ChatBot?

A chatbot (or bot) is a conversational software agent designed to chat with humans via voice or text. It may be smart, it may be dumb. It may understand random input, it may not even allow that to happen!

Why Have a ChatBot?

Availability: ChatBots don’t sleep or get sick. They just live on all your platforms and answer queries even when your people are all away. Performance: You need not to hire more staff to address more queries. ChatBots are easily to replicate using cloud based servers. This allows you to address more prospects and convert more of them into customers. Understanding: Every session is logged and you can aggregate sessions to better analyse what is going on with your visitors, who they are, what they want. Reduced Costs: Apart from the initial investment and ongoing server costs, you a fixed cost solution. Improved Customer Service: ChatBots are versatile, and can be used on anytime, anywhere. Your customers and prospects can access valuable information when they want to, not when it suits you!.

What is a Rules-based or Rule-based ChatBot?

A rule-based chatbot can answer questions using a pre-defined set of rules. The set of rules can greatly vary in complexity. Building rule-based bots is much simpler than building AI bots. Rule-based bots are generally faster to train. Rule-based bots can recommend actions based on the outcome of the conditional statements in their rulesets. These bots cannot learn on their own and will provide the answers that the companies want them to provide. Since rule-based bots cannot self-learn, this ensures that they will provide consistent customer service. Rule-based bots can professionally hand over the conversation to a human agent if the customer asks something that is absent from the database.

Document Assembly

What is Document Generation or Document Assembly?

Document Generation refers to the ability to generate document instances from a generic document template. In order to generate a document, the user is prompted for information and choices needed to assemble the final product using data collected during the user's session. VisiRule supports Automated Document Generation by providing various specific tags which can be used inside a Word or RTF template. When a VisiRule session completes, VisiRule will use the tags to propagate the answers from the session into the template, dragging through any associated text fragments, and produce a fully instantiated document instance.


Can AI systems explain their answers?

Rule-based AI systems, such as expert systems, can explain their reasoning by walking through the rules that were used to reach the conclusion. Such explanations can be provided in the form of a document which contains the portions of legal advice/guidance triggred by the specific rules or in the form of an interactive chatbot.

What is Artificial Intelligence?

Artificial Intelligence, or AI, is a much maligned term which refers to an approach to computing which tries to model some of the advanced cognitive functions of humans. Typically, AI systems aspire to emulate the reasoning of human experts who can perform quite complicated and specialist tasks, normally after years of training and practice. Recently, AI has become almost exclusive associated with Deep Learning, which itself uses a suite of a mathematically based algorithms that can be taught or trained how to achieve results which are comparable to those of skilled human operators.

NoCode LowCode

What does No-Code Low-Code mean?

A low-code/no-code development platform is a highly visual development environment that allows non-programmers to develop applications simply by dragging and dropping certain visual components, linking them together and where needed, adding bits of text to customise their behaviour. This allows 'normal' people to create a mobile or web app.

How does Visual Development work?

Visual development provides a more intuitive way to build applications. Using a decsion tree flowchart development concepts to visually define the user interaction, decision logic, and data model, VisiRule enables a spectrum of developers from citizen developers to domain experts to application developers to develop mobile applications, web applications, APIs, microservices, and much more. Because the development environment is highly visual, authors gain proficiency in a fraction of the time it takes to master a traditional language or programming suite. And, if hand coding is required, VisiRule allows professional developers to incoprtae custom logic and functionalityusing Prolog and Flex.

What is Diagramming Software?

Diagramming software allows users to create detailed diagrams, such as flow charts and floor plans, with a dedicated drawing tool. Most diagramming software tools are limited in that all they can produce are pretty pictures, ideal for visualization and presenations. VisiRule is unusual in that VisiRule charts can produce executable applications in the form of expert systems.

Decision Trees

What is Decision Tree software and how is it used?

A decision tree is a flowchart-like structure in which internal node contain a "test" on an attribute (e.g. whether a coin flip comes up heads or tails), typically based on an askable question or a calculated value, each branch represents and test for the outcome, and each leaf node represents a conclusion or recommendation (i.e. a decision taken after computing all attributes)

What is a Decision Flowchart?

A decision flowchart or decision tree flow chart can help you visualise the various paths and outcomes for a particular decision you're facing. VisiRule uses decision flowcharts to capture decision logic which in turn is used to generate executable expert system software applications. These applications can be delivered by an interactive web page in the form of a guided questionnaire, or as an intelligent chatbot, or as embedded or connected components.

What is a Decision Graph vs a Decision Tree?

Decision Trees diverge at each decision point. This means that they are prone to exponential or combinatorial explosion. Imagine we have 5 questions each with 4 options, then we will have 4 ^ 5 unique branches. That's 1,024. Already hard to manage. But after just 2 more levels, we would reach 16,386; and after 2 more, 262,144. Using Decision Graphs, we can recombine divergent branches and make the maths far more manageable. This actually works very well in the real world, where there are multiple ways of getting to the same point. Indeed, in some Q&A systems, we have a lot of possible questions, but the typically user only has to answer a small number of these to reach one of a small handful of outcomes. This means that in the real world, there is a lot of natural convergence.

What is a Flow Chart?

A flowchart or flow chart, is a type of diagram that describes some sort of process. These diagrams compose of nodes or boxes, connected by links and arrows. The blocks contain information about a single step in the process. In such way, flow charts help keep the information of a process clear and concise.

What is a Decision Tree and a Decision Table?

A decision tree is a graphical representation of possible solutions to a decision based on certain conditions. A decision table is a table that indicates conditions and actions in a simplified and orderly manner. Decision trees suffer from combinatorial explosion (too many branches). Decision Tables suffer from redundancy. The only way to handle convergence in decision tables, is to use nested decision tables which comprises one of the principal advantages of decison tables, that of transparency. Note, as VisiRule diagrams support converegence, they are decision graphs.

Business Rules

What is a Business Rules Engine?

A business rule engine (BRE) is a collection of design-time and runtime software that enables businesses to define, test, edit, execute, audit and maintain a wide variety of business logic, as “Business Rules.” A business rules engine (BRE) allows non-programmers to add or change business logic in a business process management (BPM) system using a Business Rule. Business logic describes the sequence of operations that is associated with data in a database to carry out the rule. VisiRule provides a dedicated Business Rules Engine.

What are Business Rules?

A Business Rule is a statement that describes a business policy or procedure. Business Rules define some operational aspect of business logic in a non-procedural way but yet in a format which can be directly executed by a Business Rules Engine. Most companies have silos of implicit and explicit knowledge, often undocumented information, processes, and rules. The process of exposing and sharing these Business Rules across an organization creates consistency in production, processes, quality, and both customer and staff experiences. So, Business Rules can be seen both as a specification as to how an organization behaves and also serves as an executable specification with respect to the operational aspects of an organization.

What is Decision Engineering?

Decision Engineering is applying relevant knowledge to design, build, maintain, and improve systems for making decisions. Decision Engineering provides a framework that unifies a number of best practices for organizational decision making. Decision Engineering seeks to overcome a decision making "complexity ceiling", which is characterized by a mismatch between the sophistication of organizational decision making practices and the complexity of situations in which those decisions must be made. Once "engineered", decision making can be encapsulated in software systems such as VisiRule and Flex.

What is Big Data?

Big Data is a term that describes the large volumes of data - both, structured and unstructured - that a business has to deal with on a daily basis. Big Data has specific attributes called the four V’s, namely: Volume, Variety, Velocity, and Veracity.

What is Decision Automation?

Decision Automation enables organisations to automate the decision-making process. Automated decisions increase productivity and reduce risks and error rates in a decision-making process. Decision Automation combines business rules and data to make decisions in a process without the need for human intervention.