The phrase "certainly possible" is fairly common, but it strikes me as an oxymoron. Is it?
No, it's a sensible phrase that tells you two separate things: a) the speaker believes X is possible, b) the speaker is emphasizing a very high level of certainty about this belief.
There's no apparent contradiction necessary for an oxymoron because certainty and possibility are different, non-exclusive, non-dependent things. We can give an example for every combination of a level of certainty and a level of possibility:
- Solar powered air travel is certainly possible. It's not commercially viable yet, but there's a concept plane that proves it can be done.
- Hoverboards are probably possible, but I don't know how they could work except over a magnetic surface.
- Teleportation might be possible. There are a couple of mechanisms by which it theoretically might work, but it might well not actually be possible to engineer, though it's hard to see how this impossibility could ever be proved. For the foreseeable future, it'll remain a definite maybe.
- Time travel is probably impossible, it barely makes logical sense. But I'd love to be proved wrong.
- Perpetual motion machines are certainly impossible, they defy fundamental laws of physics.
Of course in day to day use, the phrase "certainly possible" is usually more about subtext, often in the context of "That's certainly possible, but not easy", where the certainty about the possibility is contrasted with some complicating factor or caveat, often to stress willingness (implying "I'm not trying to be awkward here and I do absolutely 100% agree that X is possible, but...").
- You'd like to change your booking? Of course, I'll do that right now [this is easy and routine]
- You'd like to change your booking? That's certainly possible, I'll just talk you through the procedure [I'm extremely confident it can be done, but there might be complications that might make you reconsider your choice. I'm stressing the fact it's definitely possible so you know that I'm happy to go through those complications if that's your choice, so that you don't think I'm being obstructive or trying to talk you out of it]
- You'd like to change you booking? That's probably possible, I'll just check with my supervisor [I'm not completely confident that it can be done, you should start thinking about what you will do if it is not possible]
"Certainly probable" could be argued as being an oxymoron, because like the popular oxymoron "Definitely maybe", both parts relate to probability or certainty.
But probability and possibility are different things. Successfully arguing that "certainly possible" is an oxymoron is probably impossible
I don't think it is an oxymoron. The 'certainly' does not apply to the thing that is possible - it relates to the judgement of the speaker.
So you want to build a tunnel through the mountain? I don't believe that is physically possible.
Oh I am certain it is possible - it just requires sufficient investment.
Oh it is certainly possible - it just requires sufficient investment.
I'll disagree with the other answers and argue that it is an oxymoron, in the same way that jumbo shrimp, awfully good, pretty ugly, and other classic oxymorons are. Oxymoron does not mean contradiction, it means:
a figure of speech by which a locution produces an incongruous, seemingly self-contradictory effect, as in “cruel kindness” or “to make haste slowly.”.
Note the use of the word seemingly. I think certainly possible qualifies.
Adding for emphasis: the phrase "certainly possible" seems to me to have the same constructive logic as "pretty ugly" or "awfully good", both of which are recognized by every list of oxymorons I looked at as being oxymorons.
"Certain and possible" could be interpreted as an oxymoron.1
"Certainly possible" is not.
1 Actually, depending on how strictly you use the term "possible", even this may not be so; something that is certain is generally also possible, by extension. After all, if it were not possible, how could it also be certain?
No oxymoron (there is no real or seeming contradiction), and no redundancy.
"Certainly" in the phrase marks the attitude of the speaker to the possibility or to the whole phrase.
As such, it can be seen as an intensifier:
a modifier that makes no contribution to the propositional meaning of a clause but serves to enhance and give additional emotional context to the word it modifies.
Similarly, we might say "It is quite possible." etc.
Or, one can read it as a expression of an epistemic modality, whereby it modifies not the word "possible" but the whole phrase. In a similar manner, with a phrase such as "She is going to win.", while it is perhaps true that either she is going to win or not, still there are a plethora of words or phrases that the speaker can use to express their attitude to the proposition: "Of course she is going to win." "She is perhaps going to win." etc.
A mere "It is possible." seems quite weak: it may signify lack of interest on the speaker's part. Whereas "It is certainly possible." marks the active conviction of the speaker that the event in question is possible.
Certainly possible is absolutely not an oxymoron. Using a previously referenced requirement of an "incongruous, contradictory effect," one could make cases that similar statements such as "certainly impossible" or "unlikely possible" might themselves be oxymorons. However, in order to be certain something would need first be possible, meaning that certainties are actually a subset of possibilities, i.e., part and parcel of each other. This at best speaks clearly for congruity and exhibits nothing in the way of contradiction. While initially thought provoking, the concept of a perceived oxymoron bears up to very little scrutiny in this situation.
Taking "certainly" to be the same as "necessarily", it's meaningful to say something is necessarily possible (though it is not necessarily true that it is). Since it is a truth of logic that whatever is necessarily so is possibly so, then any truth of logic will be necessarily possible, because not only is it possible, but since its possibility follows as a matter of logic, its possibility is also necessary.
Oxford Dictionaries online defines oxymoron as a “figure of speech in which apparently contradictory terms appear in conjunction.” That definition hinges on the adverb ‘apparently,’ which Oxford defines as: 1. as far as one knows or can see (Oxford defines ‘apparent’ as: 1.1. seeming real or true, but not necessarily so).
So then, according to Oxford Dictionaries online, an oxymoron is not determined by the capacity to interpret a phrase without incongruence but rather by 1) the capacity to interpret a phrase with incongruence, and 2) whether or not the incongruent possibility is employed with knowledge and intent.
To knowingly and intentionally use a phrase with incongruent potential is to employ rhetorical device, whereas to employ a phrase like ‘certainly possible’ without intending the incongruence is merely an artless or uninformed use of the language.
"Certain possibility" says that the speaker knows that the probability of something's happenning is strictly greater than nought. The speaker asserts the conditional probability, given all his/her current knowledge, is strictly positive. Almost always it also implies that they do not foresee the conditional probability's changing on the acquistion of further data. It often translates to "it is known to happen, but not always" (and, most often "known to happen, but seldom").
"Possible" unqualified betokens the speaker's belief of a positive probability, but an openness on the question of whether further data or knowledge might show the conjectured eventuality to be impossible.
However, when one gets down to subtle distinctions like this, it is almost essential to resort to strict full statements of statistical confidence levels and the knowledge/ assumptions they are conditioned on. Probability is amongst the most subtle of all concepts in science, has several like, but quite distinct meanings and its full understanding is indeed is a work in progress. See the articles "Change vs Randomness" and "Bayesian Epistemology" at the Stanford Dictionary of Philosophy.
1. Rhetoric. A pair of opposed or markedly contradictory terms placed in conjunction for emphasis.
2. Any contradiction in terms.
The second is metaphorical and irrelevant—the examples given are "the hardworking loafer that is the colonial Dutchman" (1902), "healthful Mexican food" (1989), and "affordable caviar" (1993)—but the first, the word's original sense going back to its first attestation in Servius, is concerned with intent and effect, not logical reasoning.
Logically, of course, anything certain is necessarily possible. Rhetorically, if something is certain we do n̲o̲t̲ call it "possible". "Possible" is used for expressing the contingency of a thing or state of affairs—for saying that it is not impossible but also not certain. Of course the word is being used in precisely that way in @user568458's examples above. That poster's examples switched from adverbs to "might be possible" in order to avoid the normal and parallel phrasing "possibly possible" because it points out the mistake in the reasoning being presented. "Possible" and "certain" are usually understood as intending varying degrees of certainty, not entirely separate concepts.
Oxymoron is a rhetorical term: what matters is intent and effect. For OP, if "certainly possible" sounds like an oxymoron, it is one. For, user568458, checking down a list of various degrees of possible, it isn't one.
And in fact, for most English speakers, we'll use and process the term just as user568458 described without giving it a second thought. The phrase won't be used as—or understood as—an oxymoron to most of us.
But that doesn't invalidate that there is a contradictory sense of "possible" that user568458 was denying, that there are people like the OP who will initially process the phrase on those terms, and that "certainly possible" does function as an oxymoron for them.
"Certainly possible" is not a unit, as "pretty ugly" is. When one says "it's certainly possible" the assertion that it is possible is being modified; that is, "certainly" is not a modifier of "possible"--clearer if we say "certainly it's possible". It is something of an abbreviation for "It is certain that it is possible".
- a figure of speech by which a locution produces an incongruous, seemingly self-contradictory effect, as in “cruel kindness” or “to make haste slowly.”.
The expression certainly possible does not show contradictory effects, but it may be described as a redundant expression:
- characterized by verbosity or unnecessary repetition in expressing ideas.
It is a recognizable phrase, and certainly and possible have opposite meanings. Hence, it is an oxymoron.
Oxymorons are not contradictions. "Jumbo shrimp" and "pretty ugly" are widely recognizable oxymorons. The words apply to different things. They are not contradictions; they are oxymorons.
FYI, certainly possible is a nonsensical expression when applied to a random event such as the probability of the probability being greater than 0 is 1.
But if applied to a future event with non-randomness, it makes sense.
"Can I get an A in this class?"
"It is certainly possible."
"It is probably possible."
"It might be possible."
"It is probably not possible."
"It is certainly not possible."
The expressions describe the likelihood that the student will get an A if he does everything possible to try.
"Certainly possible" is simply the speaker verifying that "yes, it is possible." Possible is yes or no, there's no "degree" of it either way. The phrase requires a target to operate properly; i.e., "What is possible?" "This is." Is it possible? Yes. So "It is certainly possible," works just fine.
My take on language/grammar is a practical one (unless it's some kind of contract/etc.). It's my language, it works for me, not I for it. Screw how the book says it should be written; if I am unclear in my meaning, that's my fault. Obey all grammar Nazi rules and still fail to communicate clearly? That's pointless legalism.
I have little use for people who communicate empty language; I communicate with language. Like a shipping container that require contents to be meaningful at its destination, it is just a container my thoughts ride in, on their way from me to you.