Smalltalk is (literally) a window on an alternative computer architecture and OS/language paradigm. There's a reason it runs on a 'virtual machine'! It's the path that computing could once have taken, the equivalent of a parallel universe: What if computers had gone with this different design; what if the language and underlying operating system were one-and-the-same... (There was even a initial attempt at object-oriented hardware: http://en.wikipedia.org/wiki/Rekursiv)
Of course, Lisp is the other example of an alternative computing ecosystem: the famous Lisp Machines, with Lispy turtles all the way down; and Interlisp, that came closest to Smalltalk's emulation of a physical machine.
Modern Smalltalk is the environment that would have emerged from this kind of platform. That it includes modern tooling and inter-operability (however limited) is a huge bonus - it represents a genuine effort to coexist with the mainstream.
That there's so much criticism of its 'image' and language syntax only drives home the absolute grip on our thinking that Algol languages and Von Neumann architectures have imposed. In my mind, that makes it an environment of inestimable value.
Ecological diversity is more than good; it's essential.
There was a third window that many people tend to forget.
Mesa/Cedar, a interactive environment first done in Mesa, the Modula-2 predecessor and later on improved as Cedar, which was a system programing language with GC!
It was a working environment similar to Interlisp-D and Smalltalk, but using dynamic libraries, an interactive debugger, REPL and lots of nice goodies for an Algol like language. Back when at AT&T green phosphor terminals were being used.
Mesa was the inspiration for Lilith operating system done in Modula-2.
Similarly Cedar was the inspiration for Oberon and its derivatives.
Using Oberon felt to certain extent like Smalltalk, in a strong typed system programming language with a GC.
But Oberon based systems had the bad luck to appear at the same time the world was paying attention to Java and rise of VMs. So just like Plan9, only a few of us enjoyed using such environments.
Of course, Lisp is the other example of an alternative computing ecosystem: the famous Lisp Machines, with Lispy turtles all the way down; and Interlisp, that came closest to Smalltalk's emulation of a physical machine.
Modern Smalltalk is the environment that would have emerged from this kind of platform. That it includes modern tooling and inter-operability (however limited) is a huge bonus - it represents a genuine effort to coexist with the mainstream.
That there's so much criticism of its 'image' and language syntax only drives home the absolute grip on our thinking that Algol languages and Von Neumann architectures have imposed. In my mind, that makes it an environment of inestimable value.
Ecological diversity is more than good; it's essential.