Great article. While there is definitely some software which needs to continually change by its very nature (think tax preparation software, where the tax laws

Great article. While there is definitely some software which needs to continually change by its very nature (think tax preparation software, where the tax laws change a bit each year), probably there are a lot more programs which could become stable and then only receive tiny fixes or tweaks every now and again. Witness what DeK did with the version numbers of TeX... Instead of counting upwards with the natural numbers, each successive version of TeX receives an added decimal digit appended on the end, which makes it approximate pi more closely. The implication is that the program is asymptotically approaching its final state, after which it will not change.