Something I’ve noticed a fair bit, recently, has been the use of the phrase “similar to” at the start of a sentence, where one would ordinarily use “like”. Say, instead of writing

Like dogs, cats have four legs.

someone would write

Similar to dogs, cats have four legs.

When I first encountered this usage, I parsed it wrong – meaning that I parsed it by the normal rules of the language, where the leading clause is a parenthetical remark that cats are similar to dogs. But as I ran into more such instances, I realized that such sentences are never meant to be parsed that way – that “similar to” is just being used as a synonym for “like”. Under the rules for “like”, the sentence is not saying that cats and dogs are similar, just that they share the property of having four legs.

Well, okay; if people want to extend the rules for “like” to “similar to”, who am I to stop them? Language changes, sometimes for the better and sometimes for the worse. But it leads to the question: what is it about “like” that is causing people to avoid it?

I have several theories:

  1. “Like” is something that, like, teenage girls say, and so is inappropriate for pompous, pedantic writing – which is commonly where I’ve seen these strange “similar to“s. In particular, I’ve seen a lot of them in formal medical and biology articles. In those fields, there are a lot of women who don’t want to seem like teenage girls in their writing. (Not that they are alone in this strange usage; males have picked it up too.)

  2. “Like” is too short and simple, and inappropriate for this era of obfuscation, so the same sorts of people who write “utilize” instead of “use” write “similar to” instead of “like”.

  3. People don’t really know where to use “like” any more, as opposed to alternatives such as “as with” or “as in”, so they just use “similar to” whenever any of them is called for, in the hope that it will do. To illustrate this distinction, the sentence

    Like everything else, the more practice you have the better you can become.

    should really be

    As with everything else, the more practice you have the better you can become.

    since “everything else” isn’t like “more practice”, “you”, or any other subpart of the sentence – not even in some particular way, as in the first example, where cats and dogs both have four legs. But it seems like some people, vaguely sensing that “like” isn’t quite the right word, would make it even worse, by writing

    Similar to everything else, the more practice you have the better you can become.

    (Not that I’ve seen that particular sentence in the wild, but I’ve seen analogous ones.) Unlike the simple substitution of “similar to” for “like”, this sort of muddling actually subtracts information as compared to a proper phrasing, so is substantially more objectionable.

These three theories are not mutually exclusive.