Stupidity: In the shuttle, when the fountain pen is floating in zero gravity, the flight attendant grabs the pen and puts it in the pocket of the sleeping passenger. She doesn't put the cap on. She puts it in his pocket nib down. Even though there is no gravity, the capillary action of the nib touching the shirt will pull the ink into his clothing and stain his shirt and jacket. (00:19:40)
Suggested correction: Who said it's a fountain pen? 2001 is set in an imaginary future with imaginary technology, one of which might be leak-proof pens.