Kurzweil says he plans to lean heavily on the Knowledge Graph to help improve natural language understanding as well.

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Those four technical challenges are: the knowledge graph, speech recognition, natural language understanding and (understanding) conversation, he said.

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And Facebook just revealed that it built a natural-language interface for its Graph Search service announced earlier this year.

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Graph Search (which I suspect was named by the engineers and nobody thought to change it) allows clear language search terms to be made to find groups of people.

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