Anonymous asks in a comment on another post:

Why do people (not just you) insist on calling it Mail.app? Every application has the .app extension. You don’t refer to Entourage as Entourage.app. We don’t call it Finder.app or Safari.app. :-) If Mail (with a capital M) is ambiguous, just use Apple Mail as you do in the sub-title of your blog.

Good question. I am familiar with this argument, put most forcefully by the universally celebrated and acclaimed Mac blogger John Gruber a few years ago.

Four thoughts occur to me:

First, I myself favour a varied and inclusive approach. On this blog you will find the app described as “Mail”, “Apple Mail” and “Mail.app”. I’m opposed to the prescriptive stance (”You may only call it / do / believe / support this one thing – or that one thing”) in general, including on this matter.

Secondly, the title “mail.app” is a title of affection, harking back to the origins of the app in NeXT. Safari and iChat do not have the same pedigree. I suppose I ought to call Dock (also part of NeXT) “Dock.app”, but I don’t feel the same affection towards that app as I do towards Mail.

Titles of affection are often idiosyncratic or irregular, and none the worse for it. I often call my son “little man” but do not feel compelled to call my daughter “little woman”. I have a pet name for my MacBook Pro, but don’t feel that I need to come up with similar names for the PCs in the house.

Thirdly, I find it hard to believe that people who are generally open-minded and generous in their worldview could – inconsistently (!) – be so narrow and ungenerous in their views on this issue. (I’m not pointing a finger at John here. My fingers aren’t pointy enough).

Fourthly, Louis Armstrong and Ella Fitzgerald put it best in a Cole Porter George Gershwin song:

You say either and I say either,
You say neither and I say neither.
Either, either,
Neither, neither,
Let’s call the whole thing off.

You like potato and I like potahto,
You like tomato and I like tomahto.
Potato, potahto,
Tomato, tomahto,
Let’s call the whole thing off.

But oh, if we call the whole thing off,
then we must part.
And oh, if we ever part,
then that might break my heart.

UPDATE: Fifthly (this didn’t occur to me), lots of people who posted comments clearly find it a useful way to counter the generic title “Mail”. Using the title “mail.app” to distinguish this mail client from other mail clients or the application from the messages, makes for more productive Google searches and greater clarity in communication.

This argument may gain extra power from Microsoft’s innovative decision to call the mail client built into Vista “Windows Mail”.