Hi,
Well, it seems that in my keenness to post I lost sight of the original thread slightly.
The original poster was asking for a suitable equivalent for "un clavo saca otro clavo"and there can be little doubt that a literal and semantic (ie conveying the same notion) equivalent would be "one nail drives out another" and, by extension of this, "one devil drives out another" and "one poison drives out another". As a previous poster mentioned, however, these proverbs don't appear to be that widely used in English.
The example I gave ("The quickest way to get over one man is to get under another one") applies specifically to relationship scenarios such as in the example quoted by the original poster, and as a translation of that particular idea, it is ideal (not to mention quite 'catchy', as proverbs tend to be). I wasn't suggesting for one moment that it's a well-known proverb in the English language (it isn't).
I said before, and I'll say again, that I personally don't like "like cures like" as an equivalent. Perhaps i'm being a little pedantic, but to me it implies some kind of symmetry, ie that an identical stimulus is required to cancel out the symptoms of the original, as is the case in homeopathy. "One nail/poison/devil drives out another" doesn't state that the nails/poisons/devils have to be identical, simply that one takes the place of the previous one, which is the essential idea. For that reason, I personally wouldn't use "like cures like" as an equivalent in a translation. I dare say there will be those who disagree with me, but then it's a free world and that's the point of a forum, is it not?
Until next time,
nmb882003