In English, the infinitive is a verb form constructed with to + the verb root, as in to read, to write, and to edit. The supposed rule against splitting an infinitive says you must not insert an adverb between to and the verb root; thus, these constructions break the rule:
- to carefully read
- to clearly write
- to thoroughly edit.
The no-split “rule” likely began as a misguided effort by early English grammarians to make English like Latin, in which the infinitive is a single word, like scribere (to write) and is therefore unsplit-able. If you can’t split infinitives in Latin, these early writers thought, then you mustn’t in English.
But English isn’t Latin. Manifestum est. In English, we have greater flexibility in placing adverbs to create desired tone and emphasis. So the “rule” is really a suggestion, and many experts say so:
“The principle of allowing split infinitives is broadly accepted as both normal and useful.” Oxford A–Z Guide to English Usage.
“It’s fine to split infinitives…. certainly don’t let anyone tell you it’s forbidden.” Mignon Fogarty in Grammar Girl’s Quick and Dirty Tips for Better Writing.
“Split infinitives … have long been an effective way to avoid awkward writing.” Jan Venolia in Write Right!
“It is permissible to split an infinitive.” Joan Magat in The Lawyer’s Editing Manual.
“There is no ‘rule’ in English about split infinitives—just the common-sense suggestion that adverbs should be placed where they sound best.” Terri LeClercq in Expert Legal Writing.
Yet after consulting a dozen sources in preparing to write this piece, I will candidly report that the predominant advice is to avoid splitting infinitives when you can. This means avoid splitting unless avoiding the split is awkward. In other words—and this is my opinion—this non-rule still has enough force that even experts who acknowledge there is no such rule advise you to follow the nonrule when you can.
My advice? Trust your ear and split the infinitive whenever splitting sounds natural to you. Although legal writing can’t always be modeled on speech, this is one area where you should write it the way you would say it.
For example, I gladly split the infinitive here:
- He asked me to carefully read the statute
And I would never write this strained, split-infinitive work-around:
- He asked me carefully to read the statute.
(It’s ambiguous, too: what’s careful, the asking or the reading?)
But avoiding the split would be simple and wouldn’t result in awkwardness or loss of emphasis:
- He asked me to read the statute carefully.
That’s a safe course if you think your reader might be a no-splitter.
Consider this awkward un-split infinitive:
- Electronic filing makes it easier for courts to locate instantly and focus on relevant portions of documents.
For me, the phrase to locate instantly and focus on is confusing. It would be better to write this:
- to instantly locate and focus on.
How about this un-split infinitive:
- A hyperlinked brief allows the judge to access quickly identified portions of the record.
I get a miscue here: to access quickly identified portions. What are the “quickly identified portions”? This is better:
- to quickly access identified portions
One more thing. Some writers take the non-rule against splitting infinitives and apply it to all verb phrases, which would mean you must not insert an adverb between an auxiliary verb and the main verb. Applying such a rule would mean verb phrases like will execute, be convinced, and have demonstrated could not be split. So all these would be wrong:
- will faithfully execute
- be easily convinced
- have publicly demonstrated
Don’t worry about splitting verb phrases. Besides the absence of a genuine rule, there’s the awkwardness of the work-arounds, as in this example I recently read:
- In recent weeks, two officials publicly have demonstrated distrust of Smith.
I hope you’ll agree the split version is more natural:
- In recent weeks, two officials have publicly demonstrated distrust of Smith.
Ultimately, the split infinitive “has become a matter of minor concern,” according to Tom MacArthur in The Oxford Concise Companion to the English Language. It ought to stay that way. If you trust your ear, you’ll probably split more than not, and that’s fine.
After all, there’s no rule against splitting an infinitive.