As simple or as simply as possible: should an adjective or adverb be used?

Solution 1:

I'd agree that with the adverb, the ambiguity does exist. But I think that the adverbial usage slants towards the 'simplest possible modelling process' rather than 'aiming for the simplest possible final model'. Adverbs are usually happiest modifying the verb.

But you can't use the adjective in your first example – the sentence would be ungrammatical; a flat adverb is sometimes available to help, but not 'simple'. And you can't use a resultative construction: 'We made the models simple' works, but 'We modelled the rockets simple' doesn't.

You have to be more wordy to disambiguate clearly, as you imply. Possibilities are:

• The rockets were modelled using the simplest modelling process possible.

or

• The rockets were modelled so as to produce the simplest models possible.

Solution 2:

In the sentence, "The rockets were modeled as simply as possible", we use "simply" since it is part of an adverbial phrase modifying the verb "modeled".

In the sentence, "The rockets were modeled to be as simple as possible", "simple" is no longer in the position of an adverb but rather an adjective because of the verb "to be".