Why did you extend an existing language instead of creating a new one?
Tom Love: That was very important because of the requirements for compatibility in large organizations. It was a very important decision early on that you could take a C program and run through the Objective-C compiler and nothing would be changed. Nothing that you could do in C would be prohibited, and nothing that you did in Objective-C would be incompatible with C. That was a big constraint, but it was a very important constraint. It allowed for mixing and matching easily, too.
Why did you choose C?
Tom: Probably because we were using Unix systems in a research environment originally and programming in C and we were trying to do things that were difficult to do in C. The August 1981 issue of Byte magazine showed up and started describing to most of the world for the first time what one could do with Smalltalk. Brad basically ...