We often encounter as used to mean because. As we know, as is not merely ambiguous: it’s hexiguous or octiguous.

I’m especially uncomfortable when I find the usage in a technical paper1, where precision (as I claim) trumps written or spoken style. I argue that as cannot stand in for because in a paper as rigorous as a specification.

But as I think about it, maybe I’m acting as a mere pedant; maybe I should lighten up a little. Do you folks think as I do? Or should I take it easy, just accept and go with it as the leaf accepts the breeze?

  1. As in the current spec for the C programming language spec, for example.
  • 2
    accept. leaf. breeze.
    – Mitch
    Mar 20, 2011 at 13:51
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    This is closely related to the question (can't find the link offhand) about using "since" to mean "because". "Since she came to the party, she must be an extrovert", causes a strange twist in the sentence if you first perceive "since" to mean "after" and then realize halfway through the sentence that it was meant as "Because".
    – Wayne
    May 12, 2011 at 17:09
  • 1
    Related: english.stackexchange.com/questions/6993/…
    – MetaEd
    Oct 4, 2012 at 13:48
  • This seems an opinion poll. (There must be factual questions about as, but this isn't one.)
    – Stuart F
    Apr 28, 2022 at 18:04

7 Answers 7


I believe using as as a mere synonym of because is quite common, especially in prose that is intentionally formulaic rather than aimed at maximum clarity, which definitely includes many technical papers.

However, several style guides deplore this usage. Fowler's Modern English Usage recommends that as should only be so used to introduce a fact well known to the reader, as a mere reminder—not to introduce an ordinary reason or argument.

Caesar's dying words to Brutus were, "you too, my son". For the record, he didn't use those exact words, as he didn't speak English.


Using as to mean because is grammatical and common. From NOAD:

as 3 because; since : I must stop now as I have to go out.

That said, as you noted it does introduce a level of ambiguity that may be out of place in a strict piece of technical writing. While it would still not be wrong, it may not communicate as clearly as some readers would like.

If you are the writer, judge for yourself whether the usage is clear. If you are the reader and encounter the ambiguity, consider looking up the material in a different source.


Sometimes writers do want the ambiguity, especially poets. Consider the opening to Fern Hill" by Dylan Thomas:

Now as I was young and easy under the apple boughs
About the lilting house and happy as the grass was green,
       The night above the dingle starry,
               Time let me hail and climb
       Golden in the heydays of his eyes

Now, as here may be read as "because" or "at the time that" or possibly other meanings. The ambiguity is one of the things that makes poetry convey so much meaning out of so few words.


I don't think we can have a problem with the use of as meaning “because” except when it causes the aforementioned ambiguities.

I teach Peruvian students in a bilingual school. They use as to mean “because” all the time because in Spanish, at least in Peru, como is used a lot more than porque. The problem, I think, only arises when, as happens frequently when I read their work, I take as to mean “because” and only realise at the end of the sentence that they meant “because”.

Taking exception to as for any other reason than this would, in my view, be pedantry.


Let me post a tangential, theoretical answer to supplement at least two other answers, already posted, with which I agree. You can make of it what you will.

Very occasionally, as might even be preferable to because, even in technical writing. The reason is as subtle as it is obscure. In a philosophical context, the Anglo-Latin stem cause can carry Aristotlean freight, implying a question as to whether the cause is material, efficient, formal or final. The Saxon conjunction as carries no such freight. The as is vaguer, of course; but English as English has its own, rather effective ways to consolidate what the French and the Greek regard as typically Saxon vagueness. The as might be all right in context.

However, my answer is merely theoretical. So far as I recall, I have never once written a sentence that simultaneously disqualified because on Aristotlean grounds and since by (as @Wayne has observed) confusion of temporal sequence (though I have several times written sentences that disqualified the one or the other); and, if I ever did write such a sentence, I probably would rewrite the whole sentence to avoid falling through to as as the third alternative. The as as a synonym for because is inadvisable because -- well, because it is inadvisable. It suggests poor education, somehow, and has long done so. I do not remember either Gibbon's or Burke's ever using as for because, for instance. If Twain put as in the mouth of a character of his, why did he do that? It never was to compliment the character's education, I don't think. That's English for you.

By the way, I very much like @Cerberus' sample sentence. It wants neither because nor since, precisely on Aristotlean and temporal grounds, whereas as works nicely there. However, that sample sentence is a rather rare case.


Going back to the example: For the record, he didn't use those exact words, as he didn't speak English. This may be grammatically correct, but I would contend that a good writer would never use "as" in this way. It sounds stiff. It makes the writer sound like his command of English is limited.


Simply put, AS does not mean BECAUSE. I agree that it is commonly used incorrectly. When I encounter it I think less of the author's writing ability and knowledge of the language. I do not want to sound like a snob, it's just the way I feel. Using AS for BECAUSE reads like someone who is trying to present as a sophisticated writer but is usually far from it.

  • This is more a comment than an answer. :)
    – Ronan
    Mar 13, 2014 at 17:05

Soitainly! There aint no problem usin' "as" for "because" because "as" not only sounds right and is clearly an acceptable alternative to "because" but it adds an added dimension to the sentence that cannot be found with "because" because "as" is only a 2-letter word (compared to the cumbersome 7-letter word "because"), is made up of 1 syllable instead of 2, like "because", which both reasons together give it an efficiency that "because" cannot offer, and finally, when it is used, with much less frequency than "because", which gives it a spicier element to whatever it's used in that "because" can never contribute, it tends to drive home the meaning of the whole sentence with the force of a Yaz homerun that "because" generally is unable to do!

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