(defobs 1.00 "icecream is cold"
  (exists-property-with-value 'icecream 'cold))

(defobs 1.00 "earth is a planet"
  (pertenence-to-group 'earth 'planet))

(defobs 1.00 "Green is a color"
  (pertenence-to-group 'green 'color))

(defobs 1.00 "airplanes do fly"
  (exists
   (capacity 'airplane 'fly)))

;; (defobs 1.00 "Is it hot during the summer?"
;;   (question
;;    (during 'summer
;;            (exists-property-with-value
;;             'context 'hot))))

;; (defobs 1.00 "is chile in south america ?"
;;   (question
;;    (pertenence-to-group 'chile 'south-america)))

;; (defobs 1.00 "Was Socrates a man?"
;;   (question
;;    (pertenence-to-group 'socrates 'man)))

;; (defobs 1.00 "Computers use electricity?"
;;   (question
;;    (capacity 'computer
;;              (verb 'use 'electricity))))

;; (defobs 1.00 "The dominant language in france is french?"
;;   (question
;;    (is-equal 'french
;;     (property 'france 'dominant-language))))

;; (defobs 1.00 "was abraham lincoln once president of the united states?"
;;   (question
;;     (time-frame 'past
;;                 (is-equal 'abramham-lincoln
;;                           (property 'united-states 'president)))))

;; (defobs 1.00 "Is milk white?"
;;   (question
;;    (exists-property-with-value 'milk 'white)))

;; (defobs 1.00 "do people have emotions?"
;;   (question
;;    (some-element-which-complies-with
;;     'X
;;     (element-of-group-has-property 'element 'X 'emotions))))

;; (defobs 1.00 "do objects appear smaller as they move away from you?"
;;   (question
;;    (all-element-complies-with
;;     'X
;;     (during (verb 'moving 'away)
;;             ; How to model apparence...?
;;             (exists-property-with-value 'X 'smaller)))))

;; (defobs 1.00 "Does the human species have a male and female gender?"
;;   (question
;;    (all-element-of-group-complies-with
;;     'X 'human
;;     (q-or (is-equal (property 'X 'gender) 'male)
;;           (is-equal (property 'X 'gender) 'female)))))

;; (defobs 1.00 "Is a mountain mostly made of rock?"
;;   (question
;;    (all-element-of-group-complies-with
;;     'X 'mountain
;;     (is-equal 'rock
;;               (property 'X 'made-of)))))

;; (defobs 1.00 "is sun microsystems a computer company?"
;;   (question
;;    (pertenence-to-group
;;     'sun-microsystems
;;     'computer-company)))

;; (defobs 1.00 "Do you see with your eyes and smell with your nose?"
;;   (question ; How to model reflectiveness... ?
;;             (q-and (exists (capacity 'eyes 'see))
;;                    (exists (capacity 'nose 'smell)))))

;; (defobs 1.00 "Is smoking bad for your health?"
;;   (question ; How to model reflectiveness again...?
;;             (implies (verb 'smoke '())
;;                      (property 'health 'bad))))

;; (defobs 1.00 "Does a dog have four legs?"
;;   (question
;;    ; How to separate quantity from property... ?
;;    (is-equal 'four
;;              (quantity
;;               (property
;;                'dog
;;                'leg)))))

;; (defobs 1.00 "Do mammals have hearts?"
;;   (question
;;    (all-element-of-group-complies-with
;;     ; Properties don't quite fit...
;;     'X 'mammal
;;     (exists-property-with-value 'X 'heart))))

;; (defobs 1.00 "is the Earth a planet?"
;;   (question
;;    (pertenence-to-group 'earth 'planet)))

;; (defobs 1.00 "Is water a liquid?"
;;   (question
;;    (pertenence-to-group 'water 'liquid)))

;; (defobs 1.00 "Is Bugs Bunny a cartoon character?"
;;   (question
;;    (pertenence-to-group 'bugs-bunny 'cartoon-character)))

;; (defobs 1.00 "Do Humans communicate by Telephone?"
;;   (question
;;    ; How to model communication means... ?
;;    (some-element-which-complies-with
;;     'X
;;     (property 'X 'communicate-by))))

;; (defobs 1.00 "is beer a drink ?"
;;   (question
;;    (pertenence-to-group 'beer 'drink)))

;; (defobs 1.00 "are there 12 months in a year?"
;;   (question
;;    (is-equal 12
;;              (quantity (property 'year 'month)))))

;; (defobs 1.00 "does the sun hurt your eyes when you look at it?"
;;   (question ; How to model reflectiveness again... ?
;;             (implies (verb 'look '(sun))
;;                      (exists-property-with-value 'eyes 'hurt))))

;; (defobs 1.00 "Do most cars have doors?"
;;   (question ; How to define probability... ?
;;             (element-of-group-has-property 'x 'car 'door)))

;; (defobs 1.00 "is orange both a fruit and a colour?"
;;   (question
;;    (q-and
;;     (pertenence-to-group 'orange 'fruit)
;;     (pertenence-to-group 'orange 'color))))