Почему не работает функция onEat()? (Elementary JS)

     class Human {
      constructor(props = {}) {
        this.name = props.name || "No name"
        this.height = props.height || 80;
        this.weight = props.weight || 65;
        this.mood = props.mood || 'sad';
        this.hungry = props.hungry || true;
        this.tired = props.tired || false;
        this.friends = [];
        this.onEat = function () {}
      };
      seat() {
          console.log('sitting');
       };
       addFriend (friend) {
          this.friends.push(friend);
          this.say('awesome, I have a new friend');
       };
       deleteFriend (friend) {
          this.friends.pop(friend);
       };
       say (text) {
          console.log( this.name + " says: " + text )
       }
       eat () {
          this.hungry = 'false';
          this.say('I am not hungry now!');
        }
    };
    const gordon = new Human({
      name: 'Gordon',
      hungry: false,
      weight: 80,
      mood: 'old man'
    });
    const adam = new Human({
      name: 'Adam',
      height: 185,
      weight: 85,
      mood: 'augment',
      onEat: function () {
        gordon.say('fuck, i want eat too')
        }
    });
    const gerald = new Human ({
      name: 'Gerald',
      height: 190,
      weight: 80,
      mood: ' witcher',
      hungry: false,
      tired: true
     });
    adam.eat();