diff --git a/prepare/src/main/guessNNprepare/Main.scala b/prepare/src/main/guessNNprepare/Main.scala
index 95ac12c..01a94ce 100644
--- a/prepare/src/main/guessNNprepare/Main.scala
+++ b/prepare/src/main/guessNNprepare/Main.scala
@@ -1,6 +1,6 @@
 package guessNNprepare
 
-import guessNNprepare.mains.ExtractEntities
+import guessNNprepare.mains.{ComputeConcepts, ExtractEntities}
 import net.sourceforge.argparse4j.ArgumentParsers
 import net.sourceforge.argparse4j.inf.{ArgumentParser, ArgumentParserException, Namespace}
 
@@ -9,12 +9,14 @@ object Main {
 		val parser: ArgumentParser = ArgumentParsers.newFor("GuessNN-prepare").singleMetavar(true).build()
 		val subParsers = parser.addSubparsers().dest("command").title("Commands").metavar("COMMAND").help("Command to execute")
 		ExtractEntities.addCliArgs(subParsers.addParser("entities").help(ExtractEntities.description))
+		ComputeConcepts.addCliArgs(subParsers.addParser("concepts").help(ComputeConcepts.description))
 
 		try {
 			val ARGS: Namespace = parser.parseArgs(args)
 			val command = ARGS.getString("command")
 			command match {
 				case "entities" => ExtractEntities.execute(ARGS)
+				case "concepts" => ComputeConcepts.execute(ARGS)
 				case _ =>
 					System.err.printf(s"Unknown command ${command}");
 					System.exit(1)
diff --git a/prepare/src/main/guessNNprepare/Utils.scala b/prepare/src/main/guessNNprepare/Utils.scala
new file mode 100644
index 0000000..e4a1371
--- /dev/null
+++ b/prepare/src/main/guessNNprepare/Utils.scala
@@ -0,0 +1,25 @@
+package guessNNprepare
+
+import org.json.JSONArray
+
+import java.util.stream.StreamSupport
+import scala.jdk.StreamConverters.StreamHasToScala
+import scala.util.{Failure, Success, Try}
+
+object Utils {
+
+	def JSONArrayElementsAs[T](array: JSONArray): Seq[T] = {
+		StreamSupport.stream(array.spliterator(), false).toScala(LazyList)
+			.map(obj => obj.asInstanceOf[T])
+	}
+
+	/**
+	 * Convert a list of Try to a Try of a list. The Try is a failure if <em>any</em> element in the list of a failure.
+	 */
+	def flattenTryList[T](l: List[Try[T]]): Try[List[T]] = l match {
+		case Failure(e) :: _ => Failure(e)
+		case Success(value) :: rest => flattenTryList(rest).map(r => value :: r)
+		case Nil => Success(Nil)
+	}
+
+}
diff --git a/prepare/src/main/guessNNprepare/mains/ComputeConcepts.scala b/prepare/src/main/guessNNprepare/mains/ComputeConcepts.scala
new file mode 100644
index 0000000..818ec22
--- /dev/null
+++ b/prepare/src/main/guessNNprepare/mains/ComputeConcepts.scala
@@ -0,0 +1,46 @@
+package guessNNprepare.mains
+
+import guessNNprepare.{NamedEntity, Utils}
+import net.sourceforge.argparse4j.impl.Arguments
+import net.sourceforge.argparse4j.inf.{ArgumentParser, Namespace}
+import org.json.{JSONArray, JSONObject, JSONTokener}
+
+import java.nio.file.{Files, Path, Paths}
+import scala.util.Try
+
+object ComputeConcepts extends MainCommand {
+	override def description: String = "Compute the CNN for a given goal entity"
+
+	override def addCliArgs(parser: ArgumentParser): Unit = {
+		parser.description(description)
+
+		parser.addArgument("guessable_entities").`type`(Arguments.fileType().verifyCanRead()).help("JSON file containing all guessable entities")
+	}
+
+	override def execute(ARGS: Namespace): Unit = {
+		// CLI args
+		val entitiesFilePath = Paths.get(ARGS.getString("guessable_entities"))
+
+		println(s"Loading entities from ${entitiesFilePath}")
+		val entities: List[NamedEntity] = loadEntitiesOrFail(entitiesFilePath)
+		println(s"Loaded ${entities.length} entities")
+
+
+	}
+
+	private def loadEntitiesOrFail(jsonFilePath: Path): List[NamedEntity] = {
+		Try(new JSONArray(new JSONTokener(Files.newInputStream(jsonFilePath))))
+			.map(arr =>
+				Utils.JSONArrayElementsAs[JSONObject](arr)
+					.map(NamedEntity.apply)
+					.toList
+			)
+			.flatMap(Utils.flattenTryList)
+			.recover(err => {
+				System.err.println(s"Error when parsing entities: ${err}")
+				System.exit(1)
+				Nil
+			})
+			.get
+	}
+}