# Is the usage of “vice versa” appropriate in academic writing?

I have written:

In an oil-water system, if the particle contact angle is larger than 90°, showing greater affinity for the oil phase, then the system is likely to be a W/O emulsion and vice versa.

Does this convey "if the particle contact angle is lower than 90°, that the system is more likely to be O/W emulsion", in a more professional way, or does it seem lazy?

I hate writing repeating sentences, with a few different words.

• "W/O" seems a bit close to the common shorthand for "without", "w/o". – Nat Feb 2 '18 at 8:03
• Not my field, but IMHO that's not clear. In particular, it seems not clear whether the "vice versa" relates to the angle, the affinity, or the oil-water (water/oil) part. – tobias_k Feb 2 '18 at 10:39
• @tobias_k: Good point. Also, for some readers, it will not be clear whether "showing greater affinity for the oil phase" is AN ADDITIONAL ASSUMPTION that is to be included with the contact angle assumption, or this is simply pointing out a A CONSEQUENCE of the contact angle assumption. A possible fix: (1) If this is an additional assumption, then replace "larger than 90°, showing" with "larger than 90° and the system shows". (2) If a consequence of the contact angle assumption, then replace "larger than 90°, showing" with "larger than 90°, and hence the system shows". – Dave L Renfro Feb 2 '18 at 11:26
• No. The viceversa in the block sentence does not reverse W/O. It just means that if you have W/O than likely the contact angle is larger than 90 deg. In academy and outside. And adding a comma changes nothing, in this regard. – Alchimista Feb 8 '18 at 9:39

I think there should be a comma before "and vice versa".

While a person with more subject area knowledge might have taken your intended meaning, I read it as "In an oil-water system, if the particle contact angle is larger than 90°, showing greater affinity for the oil phase, then the system is likely to be a W/O emulsion, and if the system is a W/O emulsion, then it is likely that the particle contact angle is larger than 90°". The term "vice versa' generally refers to reversing between the terms, not reversing within the terms. So I think it's not so much that "vice versa" in general is inappropriate in academic writing as that you are not using the term correctly.

A correct formulation would be "An oil-water system with a particle contact angle larger than 90°, and one with angle less than 90°, are, respectively, likely to be a W/O emulsion, and an O/W emulsion". Or "In an oil-water system, larger contact angles show greater affinity for the oil phase, and crossing from less than 90° to greater than marks a transition from O/W emulsion being more likely to W/O being so."

I would make the position completely clear:

Conversely, if the angle is …

technical writing is not a good place to leave people guessing or admitting the possibility of ambiguity: for a few extra words it is worth it IMHO...

• I would think that this does not rule out the possibility of using 'vice versa' in good technical writing when the point can be made clearly (which seems quite doable in a less complicated sentence structure). But I fully agree that much time and effort should be spent making your point clear to a reader (not yourself). – Jon Custer Feb 2 '18 at 14:27