23 ms·

The Deep Insights of Alan Kay (2013)

64 points by plurby 11y ago

deleted 11y ago
[deleted]
ZenoArrow 11y ago
"And that they did, which saw through the creation of the impressive array of technologies invented at PARC which were the foundations for much of personal computing and programming as we know it today, including: •Laser Printers •Object Oriented Programming / Smalltalk •Personal Computers •Ethernet / Distributed Computing •GUI / Mouse / WYSIWYG" The work done at PARC was clearly influential, but mostly as a refinement of what came before. They were clearly building on the work of Engelbart and his team at Stanford. In fact, if I remember correctly, some members of that team ended up working at Xerox PARC. In case this is new information to anyone, search on Google for 'The Mother Of All Demos'.
mythz 11y ago
Big takeaways from this is that unnecessary complexity is stalling software engineering as a discipline which is bounded by human fragility and the limited "complexity budget" that the human mind can withhold. The Big Idea of Object Oriented Programming is "Messaging" and encapsulation, i.e. how objects encapsulate their internal complexity and expose their capabilities for maximum re-use and minimal knowledge and coupling of internals. TCP/IP is Real Computers All The Way Down (RCATWD) and is possibly the only real object-oriented system in working order where its level of complication is balanced by its level of complexity, which retain the semantics of real objects in which the basic unit of computation is a whole computer. "The Web, in comparison, is a joke. The Web was done by amateurs." RPC distorts developer mindsets by focusing on thinking of making a "remote call" instead of thinking of remote endpoints as (RCATWD) objects and focusing on instead of communication of messages and what optimal messaging API designs Services should expose for maximum encapsulation and re-use of their capabilities.
- pacala 11y ago
  > The Big Idea of Object Oriented Programming is "Messaging" and encapsulation, i.e. how objects encapsulate their internal complexity and expose their capabilities for maximum re-use and minimal knowledge and coupling of internals. Encapsulation is what people have done since the dawn of time. Mathematics is essentially a system for "encapsulating internal complexity". In programming, the core abstraction mechanism is the function, which is essentially a device for "encapsulating internal complexity". OOP is a step in the wrong direction, silently exposing internal complexity via mutable state. Remove mutable state and OOP reduces to "partially applied functions" in the mathematical sense, i.e. zero original content.
  - mythz 11y ago
    "silently exposing internal complexity via mutable state" It does no such thing, OOP encapsulates both data and behavior, it encapsulates its internals and exposes an API that ensures its class invariants - there's nothing in OOP that dictates implementation or that it has to use mutable state. We're able to write larger and more complicated software because of the encapsulation possible in OOP, not in spite of it.
  - noblethrasher 11y ago
    > Mathematics is essentially a system for "encapsulating internal complexity" Not really; here's why: An index is something that maps a small space into a big one so that you can move through the big one by traversing the small one. Example: The old card catalog is a tiny space through which you can move relatively quickly so that you don't have to explore parts of the library through which you can only move relatively slowly. Mathematics is an indexing system for ideals (it maps ideals onto ideals). It's unreasonably effective for a couple of reasons: * Some ideals correspond close enough to reality to be useful. So, mathematics indexes reality. * Since mathematics indexes ideals, it can index itself. In other words, no matter how big mathematics gets, you can always shrink it again by using more math. The purpose of encapsulation is to hide, but the purpose of indexing is to reveal. Mathematics does the opposite of encapsulation. > In programming, the core abstraction mechanism is the function, which is essentially a device for "encapsulating internal complexity" Abstraction is not about hiding complexity, abstraction is just naming things. I think what you really mean to say is that the core abstraction in programming is substitution: We give names to substitutions. (As a side note, it's an unfortunate misconception that software must have complexity which must then be hidden) > Remove mutable state and OOP reduces to "partially applied functions" in the mathematical sense, i.e. zero original content. Remove mutable state and de facto OOP reduces de jure OOP, which reduces to "networks of general purpose computers that get things done by sending and interpreting messages". We have at least one big existence proof that this works at scale. But, even in the mathematical sense, OOP with immutability offers more than just partial function application; it yields families of algebras, and we're always inventing/discovering new varieties of those. On the other hand, if you use just a little bit of mutable state judiciously, you get a set of propositions that are falsifiable by experiment: In other words, you get science, which was one of the motives for inventing OOP.
dang 11y ago
Discussed in 2013: https://news.ycombinator.com/item?id=5293152 https://news.ycombinator.com/item?id=5293152.

64 points by plurby 11y ago

deleted 11y ago

[deleted]

"And that they did, which saw through the creation of the impressive array of technologies invented at PARC which were the foundations for much of personal computing and programming as we know it today, including: •Laser Printers •Object Oriented Programming / Smalltalk •Personal Computers •Ethernet / Distributed Computing •GUI / Mouse / WYSIWYG" The work done at PARC was clearly influential, but mostly as a refinement of what came before. They were clearly building on the work of Engelbart and his team at Stanford. In fact, if I remember correctly, some members of that team ended up working at Xerox PARC. In case this is new information to anyone, search on Google for 'The Mother Of All Demos'.

mythz 11y ago

Big takeaways from this is that unnecessary complexity is stalling software engineering as a discipline which is bounded by human fragility and the limited "complexity budget" that the human mind can withhold. The Big Idea of Object Oriented Programming is "Messaging" and encapsulation, i.e. how objects encapsulate their internal complexity and expose their capabilities for maximum re-use and minimal knowledge and coupling of internals. TCP/IP is Real Computers All The Way Down (RCATWD) and is possibly the only real object-oriented system in working order where its level of complication is balanced by its level of complexity, which retain the semantics of real objects in which the basic unit of computation is a whole computer. "The Web, in comparison, is a joke. The Web was done by amateurs." RPC distorts developer mindsets by focusing on thinking of making a "remote call" instead of thinking of remote endpoints as (RCATWD) objects and focusing on instead of communication of messages and what optimal messaging API designs Services should expose for maximum encapsulation and re-use of their capabilities.

pacala 11y ago
> The Big Idea of Object Oriented Programming is "Messaging" and encapsulation, i.e. how objects encapsulate their internal complexity and expose their capabilities for maximum re-use and minimal knowledge and coupling of internals. Encapsulation is what people have done since the dawn of time. Mathematics is essentially a system for "encapsulating internal complexity". In programming, the core abstraction mechanism is the function, which is essentially a device for "encapsulating internal complexity". OOP is a step in the wrong direction, silently exposing internal complexity via mutable state. Remove mutable state and OOP reduces to "partially applied functions" in the mathematical sense, i.e. zero original content.
- mythz 11y ago
  "silently exposing internal complexity via mutable state" It does no such thing, OOP encapsulates both data and behavior, it encapsulates its internals and exposes an API that ensures its class invariants - there's nothing in OOP that dictates implementation or that it has to use mutable state. We're able to write larger and more complicated software because of the encapsulation possible in OOP, not in spite of it.
- noblethrasher 11y ago
  > Mathematics is essentially a system for "encapsulating internal complexity" Not really; here's why: An index is something that maps a small space into a big one so that you can move through the big one by traversing the small one. Example: The old card catalog is a tiny space through which you can move relatively quickly so that you don't have to explore parts of the library through which you can only move relatively slowly. Mathematics is an indexing system for ideals (it maps ideals onto ideals). It's unreasonably effective for a couple of reasons: * Some ideals correspond close enough to reality to be useful. So, mathematics indexes reality. * Since mathematics indexes ideals, it can index itself. In other words, no matter how big mathematics gets, you can always shrink it again by using more math. The purpose of encapsulation is to hide, but the purpose of indexing is to reveal. Mathematics does the opposite of encapsulation. > In programming, the core abstraction mechanism is the function, which is essentially a device for "encapsulating internal complexity" Abstraction is not about hiding complexity, abstraction is just naming things. I think what you really mean to say is that the core abstraction in programming is substitution: We give names to substitutions. (As a side note, it's an unfortunate misconception that software must have complexity which must then be hidden) > Remove mutable state and OOP reduces to "partially applied functions" in the mathematical sense, i.e. zero original content. Remove mutable state and de facto OOP reduces de jure OOP, which reduces to "networks of general purpose computers that get things done by sending and interpreting messages". We have at least one big existence proof that this works at scale. But, even in the mathematical sense, OOP with immutability offers more than just partial function application; it yields families of algebras, and we're always inventing/discovering new varieties of those. On the other hand, if you use just a little bit of mutable state judiciously, you get a set of propositions that are falsifiable by experiment: In other words, you get science, which was one of the motives for inventing OOP.

dang 11y ago

Discussed in 2013: https://news.ycombinator.com/item?id=5293152 https://news.ycombinator.com/item?id=5293152.