The White Knight Explains Pointers

In The Guerrilla Guide to Interviewing, Joel Spolsky describes the difficulty that some programming students have understanding pointers
...understanding pointers in C is not a skill, it's an aptitude. In Freshman year CompSci, there are always about 200 kids at the beginning of the semester, all of whom wrote complex adventure games in BASIC for their Atari 800s when they were 4 years old. They are having a good ol'; time learning Pascal in college, until one day their professor introduces pointers, and suddenly, they don't get it. They just don't understand anything any more. 90% of the class goes off and becomes PoliSci majors, then they tell their friends that there weren't enough good looking members of the appropriate sex in their CompSci classes, that's why they switched. For some reason most people seem to be born without the part of the brain that understands pointers. This is an aptitude thing, not a skill thing--it requires a complex form of doubly-indirected thinking that some people just can't do.

Perhaps these students should log out and try reading Alice Through the Looking Glass. In Chapter VIII, the White Knight explains pointers

'You are sad,' the Knight said in an anxious tone: 'let me sing you a song to comfort you. The name of the song is called "HADDOCKS' EYES."'
'Oh, that's the name of the song, is it?' Alice said, trying to feel interested.
'No, you don't understand,' the Knight said, looking a little vexed. 'That's what the name is CALLED. The name really IS "THE AGED AGED MAN."'
'Then I ought to have said "That's what the SONG is called"?' Alice corrected herself.
'No, you oughtn't: that's quite another thing! The SONG is called "WAYS AND MEANS": but that's only what it's CALLED, you know!'
'Well, what IS the song, then?' said Alice, who was by this time completely bewildered.
'I was coming to that,' the Knight said. 'The song really IS "A-SITTING ON A GATE": and the tune's my own invention.'

Steven W. McDougall / resume / swmcd@world.std.com / 2003 November 27