Why use Ruby instead of Smalltalk?

I'm more of a Pythonista than a Ruby user, however the same things hold for Ruby for much the same reasons.

• The architecture of Smalltalk is somewhat insular whereas Python and Ruby were built from the ground up to facilitate integration. Smalltalk never really gained a body of hybrid application support in the way that Python and Ruby have, so the concept of 'smalltalk as embedded scripting language' never caught on.
  
  As an aside, Java was not the easiest thing to interface with other code bases (JNI is fairly clumsy), but that did not stop it from gaining mindshare. IMO the interfacing argument is significant - ease of embedding hasn't hurt Python - but this argument only holds moderate weight as not all applications require this capability. Also, later versions of Smalltalk did substantially address the insularity.

• The class library of most of the main smalltalk implementations (VisualWorks, VisualAge etc.) was large and had reputation for a fairly steep learning curve. Most key functionality in Smalltalk is hidden away somewhere in the class library, even basic stuff like streams and collections. The language paradigm is also something of a culture shock for someone not familiar with it, and the piecemeal view of the program presented by the browser is quite different to what most people were used to.
  
  The overall effect is that Smalltalk got a (somewhat deserved) reputation for being difficult to learn; it takes quite a bit of time and effort to become a really proficient Smalltalk programmer. Ruby and Python are much easier to learn and to bring new programmers up to speed with.

• Historically, mainstream Smalltalk implementations were quite expensive and needed exotic hardware to run, as can be seen this net.lang.st80 posting from 1983. Windows 3.1, NT and '95 and OS/2 were the first mass market operating systems on mainstream hardware capable of supporting a Smalltalk implementation with decent native system integration. Previously, Mac or workstation hardware were the cheapest platforms capable of running Smalltalk effectively. Some implementations (particularly Digitalk) supported PC operating systems quite well and did succeed in gaining some traction.
  
  However, OS/2 was never that successful and Windows did not achieve mainstream acceptance until the mid 1990s. Unfortunately this coincided with the rise of the Web as a platform and a large marketing push behind Java. Java grabbed most of the mindshare in the latter part of the 1990s, rendering Smalltalk a bit of an also-ran.

• Ruby and Python work in a more conventional toolchain and are not tightly coupled to a specific development environment. While the Smalltalk IDEs I have used are nice enough I use PythonWin for Python development largely because it has a nice editor with syntax highlighting and doesn't get underfoot.
  
  However, Smalltalk is was designed to be used with an IDE (in fact, Smalltalk was the original graphical IDE) and still has some nice features not replicated by other systems. Testing code with highlight and 'Show it' is still a very nice feature that I have never seen in a Python IDE, although I can't speak for Ruby.

• Smalltalk was somewhat late coming to the web application party. Early efforts such as VisualWave were never terribly successful and it was not until Seaside came out that a decent web framework got acceptance in Smalltalk circles. In the meantime Java EE has had a complete acceptance lifecycle starting with raving fanboys promoting it and finally getting bored and moving onto Ruby ;-}
  
  Ironically, Seaside is starting to get a bit of mindshare among the cognoscenti so we may find that Smalltalk rides that cycle back into popularity.

Having said that, Smalltalk is a very nice system once you've worked out how to drive it.

When I leave my house in the morning to go to work, I often struggle with the decision to make a left or right turn out of my drive way (I live in the middle of a street). Either way will get me to my destination. One way leads me to the highway which, depending on traffic, will probably get me to the office the quickest. I get to drive very fast for at least part of the way and I have a good chance of seeing a pretty girl or two on their way to work :-)

The other way allows me to travel down a very enchanting, windy back road with complete tree cover. That path is quite enjoyable and of the two approaches is definitely the more fun, though it means that I will get to the office later than I would have had I taken the highway. Each way has its merits. On days that I am in a big hurry, I will usually take the highway though I may run into traffic and I also increase my chances of getting into an accident (if I am not careful in my haste). Other days I may choose the woody path and be driving along, enjoying the scenery and realize that I am running late. I may try to speed up, raising my chances of getting a ticket or causing an accident myself.

Neither way is better than the other. They each have their benefits and risks, and each will get me to my goal.

I think your question is somewhat missing the point. You shouldn't choose, you should learn them both!

If you truly are in a position that you can choose the next framework(vm, infrastructure) then you need to decided what to use and can ask a specific question with pros and cons from the perspective of what your application is inteded to do.

I have used smalltalk (love it) and ruby (love it).

At home or for open source project I can use every language I like, but when doing work I have to adopt.

I started to use ruby (at work) because we needed some scripting language that behaved more-or-less equally under solaris,linux and windows(98,2000,xp). Ruby was at that time unknown to average-joe and there didn't exist any rails. But it was easy to sell to everyone involved.

(Why not python? the truth ? I once spend a week hunting for a bug that happened when a terminal converted my space to a tab and the intending got messed up).

So people started to code more and more in ruby because it was so relaxing, enjoying and not a cloud on the sky.

Paul Graham sums it up

It's true, certainly, that most people don't choose programming languages simply based on their merits. Most programmers are told what language to use by someone else.

and

To be attractive to hackers, a language must be good for writing the kinds of programs they want to write. And that means, perhaps surprisingly, that it has to be good for writing throwaway programs.

And when were at the Lisp land try to replace LISP with smalltalk

Ruby’s libraries, community, and momentum are good

So if LISP is still more powerful than Ruby, why not use LISP? The typical objections to programming in LISP are:

1. There aren’t enough libraries.
2. We can’t hire LISP programmers.
3. LISP has gone nowhere in the past 20 years.

These aren’t overwhelming objections, but they’re certainly worth considering.

and

Now, given a choice between a powerful language, and popular language, it may make excellent sense to pick the powerful one. But if the difference in power is minor, being popular has all sorts of nice advantages. In 2005, I’d think long and hard before choosing LISP over Ruby. I’d probably only do it if I needed optimized code, or macros which acted as full-fledged compilers.