Hal: Boys, this talk is very important, so I need your undivided attention. It's very important that you... [Dewey hears] be bored and squirm a lot. [reality] Now, I want to tell you about what happens when a boy really, really likes a girl. And Dewey, I'll try to make this easy for you to understand. Ah. [grabs toys]
Malcolm: [to camera] Aw, man, I still play with that.
Hal: Here we go. There's a certain thing that happens between normal, healthy people. It's called chemistry. [male toy fires gun] Well, that doesn't happen, except maybe the first time. What does happen is this: "I like you." [falsetto] "I like you, too." [normal voice] And if they love each other and take the proper precautions, they'll have sex. But I've told you about that already.
Dewey: Not me.
Hal: Well, ask your brothers. Now, unfortunately, if the boy is from our family it goes a little more like this: "I like you." "I hate you!" "Now I love you!" "Leave me alone! Your insane neediness is driving me away!" "Look at me! Look at me! Look, oh, I'm crazy! Lookit! Ooh! Ooh! Pay attention to me! Look at me! Look at me! I'm crazy! I'm an idiot! I'm an idiot! Watch me crash and burn!" [hooting] There's no explaining it. It's hereditary, and it goes back for generations. Francis has it; so does Uncle Pete. It's why your great grandpa went to work on that oil rig in Peru. All I know is your mother must carry some sort of internal antidote, because, through some fluke, I was lucky enough to get her. I just wanted you boys to know what you were in for.