I kind of agree. It was definitely a combination of those factors and a few others. I think there was an inflection point in the past ten years where performa

I kind of agree. It was definitely a combination of those factors and a few others. I think there was an inflection point in the past ten years where performance became less of an issue, allowing us to say now that performance isn't the issue it used to be. I still think that logic programming will be rediscovered as the language paradigm for the "killer app" to manage "big data." Ultimately, it felt like less of a speed problem or even a design and personnel problem than a simple matter of taste. In other words, the reason why prolog isn't more widely used is because no one _wanted_ to train people to use it, the way they trained people to use scheme, c,c++,java, and now python. For some reason, logic and logic programming was distasteful to some influential people and many unfavorable conclusions were drawn about it without much foundation, whereas similar issues in other programming paradigms tended to be glossed over. [edit] AFAIK those Japanese FG guys dispersed into academia and industry. But in the meantime, there was a development of being able to use multi-paradigm programming in a variety of languages including Java, so it's possible they are using other languages where appropriate parts of programs are written in the logic programming paradigm.