OFFICIOUSNESS

Here's something that started bothering me this morning, for no apparent reason:

Dictionaries have entries for the word 'dictionary'. Now, this in and of itself does not bother me. It's obvious that the word does not need to be there*, as the person reading the dictionary clearly already understands its function; it would be a poor choice, however, to selectively omit entries based on recursive/redundant representation. That would just provoke some idiot to come along and prove that it did need to be there. And I don't want to endure the shame of being proven wrong by an idiot.

Here is where my problem lies - Assume that a person unfamiliar with the word 'dictionary' encounters it for the first time. How can he learn, without assistance, what it means? For all intents and purposes, a dictionary has no practical ability to define itself. The person in question needs an a priori understanding of a dictionary in order to know where to look it up. That right there, is a real-world paradox. No time travel and patricide required. Thank you very much.

Here's another quickie; it's not a bothersome one, I just want to know the answer:

If you were to fill the passenger compartment of a Boeing 747 with pennies, would it be enough money to buy said airplane? My gut (which is very well fed read) tells me that it would be enough to buy several. It also reminds me that if you had the means to perform such an experiment, you can probably afford all the airplanes you want... and would probably just pay by check.

*I realize the benefit of a dictionary entry extends beyond defining a word. For example, someone may not know the spelling of the word 'dictionary'. But in counterpoint, I'll remark that opening up a dictionary and searching for it in an alphabetical list is far less efficient than, for example, reading it off the fucking cover.