Grammar quiz: Is this subject singular or plural?

"Neither the probabilities of the outcomes nor their nature (was/were) heavily constrained by the task."

I initially wrote "was", but now I'm reconsidering.

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"Generally the plan was to get away from government and allow the natural virtue of man to assert itself. What more can you ask for as an explanation of failure?" —B. F. Skinner (as Frazier in Walden Two)

I'd change "nature" to "natures" and use "were".

You've got "their" so I'd say plural. And what HeyDude said too.
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Well, there is a new accent of n00b language. It's called: Vet LUEser goes Foreign!-MegaSpy22
Those must be the pants of the gods!-Digitalpython

I'm guessing you folks are right, but…

You've got "their" so I'd say plural.

…I have a counterexample to this: "Neither the mother of the children nor their father was around."

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"Generally the plan was to get away from government and allow the natural virtue of man to assert itself. What more can you ask for as an explanation of failure?" —B. F. Skinner (as Frazier in Walden Two)

From: Kodiologist | Posted: 2/18/2013 5:52:16 PM | #004

I'm guessing you folks are right, but…

You've got "their" so I'd say plural.

…I have a counterexample to this: "Neither the mother of the children nor their father was around."

The subject of the verb is father in this case, which is singular.

In your original sentence, looks like you've got 2 subjects, outcomes and natures.
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Well, there is a new accent of n00b language. It's called: Vet LUEser goes Foreign!-MegaSpy22
Those must be the pants of the gods!-Digitalpython

Nah, the complete subject is "Neither the probabilities of the outcomes nor their nature" in the first case and "Neither the mother of the children nor their father" in the second.

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"Generally the plan was to get away from government and allow the natural virtue of man to assert itself. What more can you ask for as an explanation of failure?" —B. F. Skinner (as Frazier in Walden Two)

I'm starting to remember "neither nor" and "either or" clauses from high school, and they break the rules...so I think it's singular? I dunno anymore... You're right though, about the subjects.
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Well, there is a new accent of n00b language. It's called: Vet LUEser goes Foreign!-MegaSpy22
Those must be the pants of the gods!-Digitalpython