{ "items" : [
    { "id" : "http://dbpedia.org/resource/Variational_principle"
      "properties" : {
        "http://www.w3.org/2000/01/rdf-schema#comment" : [ "A variational principle is a scientific principle used within the calculus of variations, which develops general methods for finding functions which minimize or maximize the value of quantities that depend upon those functions."] } } }
