Change your code in smalltalk, say from "w color: black" to "w color: red". And even though the code of the program is "changed," nothing happens because the modified statement is not automatically re-executed. In a live programming system, you get useful feedback about your code edits, not just "fix and continue," and so you would immediately see affected widgets go from being black to red.

Chris Hancock's dissertation [1] is really good at making this point:

> And yet, if making a live programming environment were simply a matter of adding "continuous feedback," there would surely be many more live programming languages than we now have. As a thought experiment, imagine taking Logo (or Java, or BASIC, or LISP) as is, and attempting to build a live programming environment around it. Some parts of the problem are hard but solvable, e.g. keeping track of which pieces of code have been successfully parsed and are ready to run, and which ones haven’t. Others just don’t make sense: what does it mean for a line of Java or C, say a = a + 1, to start working as soon as I put it in? Perhaps I could test the line right away—many programming environments allow that. But the line doesn't make much sense in isolation, and in the context of the whole program, it probably isn't time to run it. In a sense, even if the programming environment is live, the code itself is not

i.e. Smalltalk code simply isn't live.

[1] http://llk.media.mit.edu/papers/ch-phd.pdf