The coordinating conjunction “but” plays the Devil’s Advocate, as it opposes the principal clause. It has many other roles, nonetheless.
The word “but” has been derived from the Anglo-Saxon “Butan.” It means except, without and outside. The prefix “be” means “by” and “atan” out.
Nevertheless, this meaning of “but” is obsolete now. Gang is but the house. Such usage of “but” remains confined to the yellow pages of a grammar book. Yet, it shows the fundamental meaning on which the accepted usage is based.
Prepositional use
When “but” is used as a preposition, it means “except” or “except for.” It raises a problem. Should we say no one but I can tell or No one can tell but me? Opinions differ.
In the first sentence many grammarians treat “but” as a conjunction. Ergo, if we go by its original meaning, “but” plays a preposition that means “outside.” Therefore, the correct form is – No one can tell but me. The meaning is clear – outside or except me.
There is, however, no clear answer in grammar. If we go by the phrase, both forms are correct. We cannot say no one but “me” can tell.
When “but” is used as a preposition, we use an object, like me, him, her, us or them. On the other hand, if “but” comes before a verb, we must use I, we, he, she or they.
I should sin to think but nobly my grandmother –
W. Shakespeare, Tempest.
In the above sentence, the Bard of Avon, as Shakespeare is known, has used “but” as a preposition “except for.”
Adversative conjunction
This is the most important role of “but”. The way this three-lettered word opposes the principal statement is loud and clear. There are many such words that express contradiction, like though, although, notwithstanding, nonetheless, save, than, unless, yet and still. As far as opposing a principal statement goes, none does it better than “but.”
Let’s see how Agatha Christie has used this adversative conjunction to give a sudden turn to a sentence.
Armstrong, after a moment of indecision, turned towards the latter.
But at that moment Rogers came quickly out of the house – Agatha Christie, AND THEN THERE WERE NONE, chapter IV (page 104).
The little “but” makes a major change to puzzle a reader.
Ernest Hemingway had the mastery to surprise his reader with “but.”
I know also about my wife – completely. But now there is always someone you do not know who loves you in ignorance and is strange to you both – Green Hills of Africa.
But at the beginning
Schoolteachers have always warned us against using “but” at the beginning of a sentence. Such a warning has no reason. It is logical to begin a sentence with “but.” If writers want to give a special staccato effect, they can use “but” at the beginning of a sentence. Else, it is better to connect two short sentences with “but.”
I will be silent. I will be invisible. But you have to eat –
Jonathan Freedman, The 3rd Woman.
“But” may also mean the adverb “only.” There is “but” one student present in the class.
William Shakespeare has used “but” in a different way.
Perdition, catch my soul, but I do love thee W. Shakespeare, Othello. Here, but means if not.
