Smalltalk’s 25th Anniversary:
The presentation marks the 25th anniversary of Smalltalk, a programming language developed by Alan Kay. Kay wrote the one-page interpreter scheme for Smalltalk 25 years ago, and the first working version was completed shortly after.

Historical Context:
Kay expresses his reluctance to give a historical talk, having recently fulfilled such obligations at the history of programming languages conference.

Visual Presentation:
Kay plans to share a series of images from 1973 and 1974 at Xerox PARC, showcasing some of the first children they worked with.

Early Programming Experiences:
Kay intends to discuss his early programming experiences and how they shaped his thinking about programming languages and tools.

“A Kid’s View of Programming”:
Kay seeks to convey a child’s perspective on programming, emphasizing the importance of simplicity, accessibility, and fun in language design.

Personal Reflections:
Kay plans to share personal reflections on the evolution of programming languages and tools over the past 25 years.

Music and the Alto Computer:
Chris Jeffers composed “The Happy Hacker” music for the Alto computer, showcasing real-time FM synthesis. The Alto computer was a forerunner of workstations and the Macintosh, featuring built-in sound synthesis capabilities.

Early OOP Experience at Xerox PARC:
Alan Kay asks the audience members who participated in the Xerox PARC Smalltalk experience between 1971 and 1983 to stand up. He acknowledges the contributions of those present and their role in shaping the early OOP landscape.

Dijkstra’s Paper on Computing Culture:
Dijkstra wrote a paper highlighting the differences between computing approaches in Europe (especially Holland) and the United States. Kay responds with a paper emphasizing that most software is written on one side of the Atlantic.

Computers as a New Kind of Math:
Kay argues that computers introduce a new kind of math that doesn’t fit well into classical math. He criticizes those who try to judge computers using classical math, calling it a form of “masturbation.”

OOP as a Blend of Beauty and Practicality:
Kay stresses the importance of balancing beauty and practicality in OOP work and programming. He believes that sacrificing either aspect undermines the true essence of computing.

The Strange Code in the Name of OOP:
Kay expresses his surprise at seeing strange-looking code labeled as OOP by various individuals, including those in academia. He clarifies that he coined the term “object-oriented,” and C++ was not his intended vision.

Smalltalk’s True Essence:
Kay emphasizes that the significance of Smalltalk and similar languages lies beyond their syntax or accumulated superclass library. He intends to focus on a critical aspect of Smalltalk that deserves close attention.

Mechanical Nature of Computing in the 1960s:
In the 1960s, computing was characterized by a sense of simple mechanism due to the large size and limited capabilities of computers. Programs were relatively small and shared similarities with their mathematical antecedents.

Programs as Interlocking Gears:
Kay compares the semantics of math programs based on logic to interlocking gears. He explains that the compatibility of components leads to the desired final outcome, akin to a real-world analogy of a doghouse.

The Flawed Approach of Scaling Up Simple Designs:
Alan Kay illustrates the problem of scaling up simple designs by using the example of a doghouse. Increasing the size of a structure by a factor of 100 leads to a million-fold increase in mass but only a ten-thousand-fold increase in strength. This results in the structure becoming weaker and collapsing.

The Common Response to Scaling Failures:
Instead of acknowledging the fundamental limitations of scaling up simple designs, people often resort to covering up the flaws with superficial additions and modifications. This approach leads to complex and fragile systems that lack integrity and resilience.

Architecture as a Solution:
Architecture involves the creation of complex structures with non-obvious interactions between simple materials, resulting in synergistic effects and increased integrity. The amount of material used in complex structures like Chartres Cathedral is often less than that used in simpler structures like the Parthenon due to clever organization and design.

Architecture’s Dominance over Material in Complex Systems:
As complexity increases, architecture becomes increasingly important in determining the success or failure of a system. Architecture enables the creation of systems that are greater than the sum of their parts, with emergent properties and behaviors.

OOP’s Lack of Focus on Architecture:
Object-oriented programming (OOP) has often neglected the importance of architecture, leading to complex and brittle systems. The recent emphasis on architecture in software design is driven by the challenges and demands of the internet.

Metaphor from “The Act of Creation”:
Alan Kay introduces the concept of “folding” as a metaphor for creating complex systems from simple components. Folding involves repeatedly combining and recombining simple elements to create increasingly complex structures with emergent properties.

Creativity as an Act of Creation:
Creativity involves learning and the emergence of something new within an individual. Alan Kay uses the metaphor of thoughts as ants crawling on a pink plane, representing a fixed context.

Progress and Optimization:
Progress within a fixed context often takes the form of optimization, as opposed to genuine creativity. Creative acts typically involve stepping outside of the existing context.

Blue Ideas and Their Emotional Responses:
Blue ideas are sudden insights or revelations that occur outside of the current context. Emotional reactions to blue ideas vary: Jokes: “ha-ha” – a sudden realization of a different meaning. Science: “aha” – a sense of discovery and understanding. Art: “ah” – an appreciation of alternative contexts.

The Role of Art:
Art serves as a reminder that there are other contexts beyond the one we are currently in. Great art takes us out of our current context and exposes us to new perspectives.

The Importance of Diverse Knowledge:
To have blue thoughts, one needs to have a diverse knowledge base and experience different things. Specialization can limit creativity by confining individuals to a single context.

Personal Experiences:
Alan Kay shares his early experiences with creativity and the concept of blue thoughts.

Emergence of Data Abstraction in the Air Force:
In 1961, an enlisted person in the Air Force developed a novel approach to managing data on magnetic tapes. The method involved dividing the tape into three parts: a header with pointers to procedures, a section with the actual data, and a middle part with procedures to handle the data formats. This approach, known as data abstraction, allowed for easier and more flexible processing of complex data formats.

Contrast with HTML on the Internet:
Alan Kay criticizes HTML for its reliance on browsers to understand its formats, likening it to a return to the “dark ages” of computing. He argues that a more effective approach would be to follow the principles of data abstraction, where the data and the procedures to handle it travel together, eliminating the need for a browser.

The Influence of Ivan Sutherland’s Sketchpad:
Ivan Sutherland’s Sketchpad, developed in the early 1960s, was an immensely sophisticated object-oriented system with concepts like classes, subclasses, and polymorphism. Kay acknowledges seeing the idea of data abstraction in various forms before, but it was only after encountering Sketchpad that he fully grasped its potential.

Simula and the Choice of Embracing Technological Advances:
Kay discusses his experience with Simula, an early object-oriented programming language. He emphasizes the importance of recognizing when a new technology represents a truly novel concept rather than just an incremental improvement. Embracing such new concepts can lead to significant breakthroughs and paradigm shifts in computing.

Inspiration from Molecular Biology:
Kay draws parallels between the development of object-oriented programming and his studies in molecular biology. He highlights the complexity of living organisms, with their intricate networks of interacting components. This biological perspective influenced his thinking about the design of computational systems, leading to the development of object-oriented programming concepts.

Complexity and Computational Power of Living Cells:
Kay describes the astonishing complexity of living cells, with their vast number of components and their ability to process information rapidly. He points out that the speed of computation in cells rivals that of modern computers, particularly considering the parallel nature of cellular processes. He uses an analogy to illustrate the remarkable speed of protein movement within cells.

Biological Complexity and Scale:
Bacteria are incredibly small, about 1,500th the size of human cells, and they can duplicate themselves in just 15 to 18 minutes under ideal conditions. Human cells are much larger and more complex than bacteria, with about 60 billion informational components compared to bacteria’s 120 million. A human body contains between 10^12 and 10^13 cells, yet only 50 cell divisions occur during a nine-month pregnancy. Over-proliferation, testing, and trimming are used to ensure that only fit cells remain in the organism.

Computers vs. Biological Systems:
Computers are often seen as slow, small, and stupid compared to biological systems due to their limited complexity and scale. Napoleon’s semaphores, a form of mechanical technology, are used as an example of a system that does not scale well. Cells, on the other hand, scale incredibly well, by factors of 100 and even trillions.

The Question:
The key question is how biological systems achieve such complexity and scale, and how we might adapt these ideas for building complex systems in technology.

Introduction:
Alan Kay highlights the importance of clear communication and the need to avoid misunderstanding when designing systems.

The Role of the Cell Membrane:
Kay explains that the cell membrane serves a dual purpose: Keeping certain things out Keeping specific things in

Challenges in Western Culture:
The Western language’s emphasis on nouns and verbs makes it difficult to express process-oriented concepts.

The Japanese Concept of Ma:
Kay introduces the Japanese concept of “ma,” which refers to the space between objects and the unseen processes that connect them. Ma is a shorter word, indicating its importance in Japanese culture.

Encapsulation and Object Behavior:
Encapsulation creates a clear interface between the inside and outside of an object. This allows an object to act like anything because it contains a computer that can be programmed to behave in specific ways.

Origins of the Encapsulation Concept:
Kay notes that the concept of encapsulation was not attributed to any particular person but was evident in early developments like Sketchpad, the Air Training Command file system, and Simula.

Design Space and OOP Languages:
Alan Kay emphasizes the significance of preserving the power of new metaphors in computer science. He criticizes data procedure languages like C++ and Java for hindering programmers’ understanding of the true strengths of the object-oriented programming (OOP) metaphor.

Virtual Machines:
Kay highlights the concept of virtual machines, which provide each user with a computer-like environment separate from the physical machine. He acknowledges Unix as an example, but notes its limitations due to the overhead of processes.

Biological Metaphor and Scaling:
Kay proposes the biological metaphor as a guiding principle for the future of computing. He emphasizes the need for commitment to this metaphor to achieve practicality at various scales.

DNA Manipulation:
Kay draws a parallel between biological systems and computer systems, noting that cystic fibrosis can be treated by infecting patients with a modified cold virus to insert a healthy gene into lung cells. He suggests that this approach could be used for reprogramming organisms’ DNA.

Objects and URLs/IPs:
Kay argues that every object on the internet should have a URL and an IP address to accurately represent its abstraction of physical hardware to bits. He views objects as servers, and polymorphism as a way to categorize these servers.

Growing vs. Building Artifacts:
Kay contrasts the ease of growing a baby with the complexity of growing a 747 aircraft due to the different design approaches. He highlights the need to consider the entire lifespan of an artifact, including maintenance, repair, and potential longevity.

Development System Constraints:
Kay questions the use of development systems that force programmers to work outside of the language itself. He suggests that such systems can limit creativity and hinder the exploration of the full potential of the programming language.

The Challenge of Building Complex Systems:
Alan Kay emphasizes the limitations of relying on compile-and-reload cycles for developing complex systems. He highlights the importance of understanding interoperability with existing systems when building complex systems.

The ARPANET as a Metaphor for Evolving Systems:
Kay shares his involvement in the design of the ARPANET, a precursor to the internet. He notes that the internet has expanded by a factor of 100 million since its inception. Kay points out that there are no original physical atoms or lines of code remaining from the original ARPANET in the current internet.

The Continuous Evolution of the Internet:
The internet has undergone constant change, replacing every atom and every bit without ever needing to stop. Kay suggests that this metaphor should be applied to smaller systems, including programming, to avoid creating large, unwieldy structures.

The Significance of Simula and Lists:
Kay highlights the importance of Simula, a programming language developed in the 1960s, and its profound insights. He emphasizes the significance of lists, a fundamental data structure, in computer science.

Java’s Reflective Model:
The reflective model of LISP written in itself on page 13 of a 1962 book contains crucial details of LISP semantics and guidelines for building a LISP interpreter. This meta-reflective aspect is essential for understanding LISP.

Java’s Lack of a Metaprogramming System:
Java initially appeared as a legitimization of the byte code approach for multi-platform compatibility. However, Java’s lack of a metasystem, including the inability to load new things during runtime, is concerning.

Java’s Pragmatic Choices:
Specific implementations of programming languages make pragmatic choices that may not cover all cases efficiently or comprehensively.

Java’s Need for Dynamic Extensibility:
Java’s lack of dynamic extensibility makes it difficult to adapt to changing requirements and interoperability needs.

Metaprogramming as a Solution:
Metaprogramming allows for dynamic modification of a program’s behavior at runtime. It enables the addition of new features, customization, and adaptation to changing conditions.

OOP Principles and Encapsulation:
Standard OOP emphasizes encapsulation to hide implementation details and allow different ways of dealing with concepts without distracting the programmer. This principle applies not only to software design but also to the design of programming languages themselves.

Language Independence and Interoperability:
The more a language can see its own structures, the more liberated it can be from the limitations of a single implementation. Interoperability between different object-oriented systems is possible by allowing each object to internalize its own local pointers to any object in the world, regardless of where it was made. This concept requires a universal interface language that is not a programming language but allows the interchange of deep information about what objects think they can do.

Importance of Universal Interface Language:
A universal interface language is critical for automating the discovery of what objects can do and for enabling safe experimentation between objects. It will revolutionize the way we operate on the internet and will supersede solutions like JavaBeans and Korba.

Recommendation for a Book on OOP:
Alan Kay highly recommends the book “Concepts, Techniques, and Models of Computer Programming” by Peter Wegner and David A. Rosenblum but criticizes its Lisp-centric and closed club-centric approach. He encourages university professors to rewrite the book in a more accessible manner for the general object-oriented community.

Abstract Data Types and C++:
In the 1970s, abstract data types emerged as a dominant paradigm, focusing on assignment-centered programming. C++ initially gained traction due to its perceived efficiency, leading to the development of operating systems like “Pink” at Apple. Kay criticizes this approach, arguing that spending years on an operating system that never works is inefficient and that Smalltalk is a better choice for rapid development.

McLuhan’s Quote and Single Points of View:
Kay emphasizes the importance of McLuhan’s quote: “I don’t know who discovered water but it wasn’t a fish,” which highlights the limitations of single points of view and belief structures. He argues that this tendency to commit to single viewpoints like religions has hindered progress in the field of computer science and in the human race in general.

Evolution of Ideas:
Kay discusses the three stages of an idea’s evolution, as described by the German philosopher Schopenhauer:
1. Denounced as the work of madmen (Confederacy of Dunces).
2. Remarked as being totally obvious the whole time.
3. Original denouncers claim to have invented it (religious stage).

Challenges Faced by Smalltalk:
Kay expresses disappointment at the challenges faced by Smalltalk after its release from Xerox PARC. He attributes some of these challenges to the perception that Smalltalk is a toy language and to the lack of support from major companies like IBM and Microsoft.

Key Points:
Smalltalk underwent significant changes and iterations during its development at Xerox PARC, with four major versions and numerous releases within a 10-year period. One of the strengths of Smalltalk was its ability to serve as a platform for bootstrapping new ideas and system-building techniques. The commercialization of Smalltalk led to a decline in its use as a vehicle for innovation and experimentation. Kay emphasizes the need for continuous thinking and exploration in systems design, rather than treating existing approaches as dogma. The goal should be to create systems that facilitate the evolution and advancement of abstraction levels. Kay’s involvement in the Squeak project aims to provide a bootstrapping mechanism for developing something better than Smalltalk. He encourages users to think of Squeak as a tool for obsoleting itself through its own mechanisms. Kay draws a parallel to the story of E. Power Biggs, a renowned pipe organist, who played grand pieces on a small organ, demonstrating the importance of playing systems “grand” to stay ahead of the future.