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I try my best to use proper sentence construction and punctuation, and for my amusement, I've taken the quest to find meaningful situations where one might use the various conjunctions at the beginning of sentences. I was told that "because" was the only one that's worthy of being placed at the start of a complete sentence. However, I've taught myself to challenge what I've been taught by attempting to discover flaws or contradictions in the logic. Along my journey, I've noticed that English is full of opposite words thus maintaining harmony and balance. By now, you should see where I'm heading with this idea; I've set out to find the inverse to the word "because." I know of the obvious examples that come to mind such as "except," "albeit," and "not because." None of these seemed to suit a universal role, though, but I believe I have discovered a solution, and I would like to know if this would be acceptable for use in sophisticated writing:
But for the faint, guiding light in the distance, the hallway was completely dark.
Which would have the same meaning as the following statement:
The hallway was completely dark but for the faint, guiding light in the distance.
Here we have the same two clauses and the same idea, but in a different order. You might observe that the phrase "but for" can be a wide-use substitute for the three examples previously listed (not directly, but in combination with other words). Please keep in mind that I follow strict guidelines, and I strive to present myself as professional as possible when conveying my ideas through language, and as such, I would prefer it if your responses would take this proposal in the same perspective.