SZTAKI HLT | 4lang


2010 -

4lang is a theory for representing language meaning and also a software library for building and working with such representations. The principal investigator of the 4lang project is Andras Kornai.


The central publications about 4lang are


The 4lang library builds and manipulates directed graphs of concepts that represent the meaning of words, phrases and sentences. 4lang can be used to

  • build concept graphs from plain text (text_to_4lang)
  • build concept graphs from dictionary definitions (dict_to_4lang)
  • measure semantic similarity of concept graphs
  • measure entailment between concept graphs (experimental)

4lang is available on GitHub under an MIT license. The repository also contains the 4lang concept dictionary.


For instructions on using 4lang, see its README


4lang was used in our system at the Semeval2015 textual similarity task, described in Recski & Ács 2015


See the README for suggestions on how to cite 4lang


The 4lang library is maintained by Gábor Recski, who can be reached at "recski at mokk dot bme dot hu".

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