More Content Areas

Survey of Knowledge Base Content

  The purpose of this lesson is to introduce you to some of the content areas in Cyc.  We have already studied the Information area.  This lesson will provide a more general overview of some of the other content areas in Cyc.


The column on the left of the slide lists some collections of emotional attributes.  The collection called #$Abhorrence includes things that are related to feelings of abhorrence. All the degrees of all of the ranges of abhorrence should be in this collection.  Entering knowledge about emotions into Cyc is facilitated by using relations like those that are listed on the right of the slide.

For instance, Cyc knows five different emotions that are related to Abhorrence with the #$contraryFeelings relation.  Three of these emotions are #$Enjoyment, #$Adulation, and #$Love.  Thus, Cyc knows that something is wrong when a person both abhors and loves a thing.

Similarly, we can tell Cyc which emotions are appropriate for a given situation according to the role that a person plays in the situation.  For instance, we can say that a given emotion is an #$AppropriateEmotion for the groom at a wedding, but not for the wedding coordinator.

Another emotion-representing relation is #$feelsTowardPersonType.  This relation allows us to tell Cyc how a person feels about a group of people.  #$actionExpressesFeeling is used to tell Cyc things like laughter expresses amusement.

Propositional Attitudes Relations Between Agents and Propositions

  Another content area in Cyc is Propositional Attitudes.  This slide lists some of the predicates that relate intelligent agents to propositions.  They are fairly self-explanatory, but we’ll discuss the #$desires relation as an example.  In the sentence “Jim desires that the sky will be cloudy,” Jim is the agent and #$desires would be used to represent the verb phrase “desires that,” which relates Jim to the proposition “the sky will be cloudy.”

Similar to relating emotion predicates to each other, we can relate propositional attitude predicates to other propositional attitude predicates.  For example, Cyc can infer that if Jim #$knows something to be true, then Jim does not hope it will be true; rather, Jim believes it is true, and it is not his goal for it to be true.


  Yet another another content area in Cyc is biology.  In Cyc, organisms are classified according to their biological taxon (such as #$Rat, #$Vertebrate, and #$Bee), their habitat (where they tend to live), and what they eat.  Some classifications are scientific, while others are not, like #$Worm.  Cyc can also take anatomical descriptions of organisms that say what organs they have and how they are related (for example, how they work in processes like metabolism and digestion).  We can even describe an organism’s life stages to Cyc.


  Cyc has a diverse Materials vocabulary for describing types of substances, physical properties of substances, and tangible attributes of substances.

You can discuss all states of matter (solid, liquid, etc.) in Cyc.  This allows us to assert, for example, that glass is classified as a solid tangible thing and yet exists in a liquid state.

Structural Attributes include things like colloid and crystalline.

Tangible attributes are used to describe the perception of how something feels.  It is important, however, to note that something that is a solid tangible thing is not necessarily in a solid state of matter.  For example, consider a piece of wood.  That piece is a solid tangible thing in that it can be touched and its shape is independent from its container, but the water that is in it is in a liquid state of matter and that water can account for 20 to 60 percent of the piece of wood.


  Cyc knows about lots of types of devices, from #$BlowDryer, #$Gun, #$Engine, #$CopyMachine, #$FishingHook, and #$Wheel, to #$AtomicClock.

Various attributes of devices can be represented within Cyc.  You can describe the state of a device, like #$PausedState, #$DeviceOn, and #$OffHook (for a phone).  You can describe actions of devices, like the spinning of a washing machine.  You can describe the power rating, operating cost, etc. of a device.  Finally, you can tell Cyc the purpose of a device with the #$PrimaryFunction predicate.  For example, the primary function of a hammer is to be used in a hitting event.


Another content area in Cyc is food.  Cyc knows a lot about food.

There are various food types in Cyc, such as the #$fruit collection, the #$meat collection, etc.

You can tell Cyc who can typically eat a food with the  #$EdibleByFn function.

#$PreparingFoodOrDrink is the collection of events that are associated with preparing a #$FoodAndDrink item (whether you start “from scratch” or use a mix).  Similarly, #$ConsumingFoodOrDrink is the collection of events in which a person or other animal ingests some portion of food or drink through its mouth

Cyc also has more specific food-related vocabulary.  For example, to say that a person is a vegetarian, you can say that he or she #$eatsWillingly #$VegetarianCuisine.


  All normal human expressions about weather, another content area in Cyc, can be expressed in CycL.

You would say that a tornado occurred on Thursday by referring to an instance of the #$TornadoAsEvent collection.

You would distinguish the snowing event from snow itself by referring to an instance of the collection called #$SnowProcess.

In order to say that a tornado hit my house on Thursday, you’d refer to an instance of the collection called #$TornadoAsObject.


  Cyc has an extensive vocabulary for describing the geography content area.

Cyc has various ways of encoding physical addresses, breaking them down into street, zip code, etc.

Cyc also has various predicates for describing characteristics of the populace like religion, language, etc.

Cyc has lots of predicates for physical relations between things (like borders), geo-political subdivisions (like voting districts), and natural land divisions (like islands and seas).

  • Emotion
  • Propositional Attitudes
  • Biology
  • Materials
  • Devices
  • Food
  • Weather
  • Geography

This concludes the lesson on additional content areas in Cyc.