The mongoose principle

The mongoose principle takes its name from an old story about a customer who wrote to a pet shop:

Dear Sirs,

Please send me two mongooses.

Yours etc.,

A. Customer.

However, on reading the letter over, the writer felt that perhaps the plural of mongoose was not mongooses, and accordingly tore the letter up and wrote the following:

Dear Sirs,

Please send me two mongeese.

Yours etc.,

A. Customer.

After a few more moments of thought, the writer felt that perhaps this was not right either, and accordingly tore this letter up as well, before writing the following:

Dear Sirs,

Please send me one mongoose.

Yours etc.,

A. Customer.

PS: On second thoughts, make it two.

The mongoose principle, therefore, states: if in difficulty or doubt, rewrite it. The principle provides a simple solution to many problems and you ignore it at your peril.