Which is correct?
We’ll _____ that bridge when we come to it.
c. jump off
Answer: It depends.
The standard expression is “cross that bridge when we come to it.” It means that you’ll deal with some potential event if and when it happens — it may not happen at all and if it does, it may be easier to see how to deal with it at that time.
“We’ll burn that bridge when we come to it” is considered to be a mixed metaphor/malaphor: an erroneous mixing of two metaphors. In this case, it’s a combination of “cross that bridge when one comes to it” and “to burn one’s bridges,” meaning to take an action that will eliminate some potential option. For example, if you toss your venti latte in the recruiter’s face at a job fair, you’re likely burning your bridges with that company. So if it may be necessary to decisively eliminate some option in the future, it would make sense to say you’ll burn that bridge when you come to it. I don’t think anyone does say that, mind you, but it would make perfect sense.
And then, of course, the other option is to jump. Site director Peggy Rouse occasionally says, when we’re discussing some deeply undesirable potential event, “Let’s jump off that bridge when we come to it.” Naturally, you don’t want to do it preemptively, as the undesirable event may never happen. And there hasn’t been anything that catastrophic yet. Should we come to the bridge we prefer not to cross, however, I picture us clasping hands like Thelma and Louise approaching that cliff and leaping. Unless we just decide to burn it instead.
So, anyway, what I’m saying is that I can see occasions for any of the three, depending on the particular bridge you’ve come to.
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