Not too long ago, Apple Computer used the phrase "Think Different" as an ad slogan. Is this a grammatical error (that is, it should be "Think Differently"), or are they trying to say something else (and what would it be)?
Merriam-Webster claim that different as an adverb dates at least as far back as 1744.
Everyone's assuming that this is "think differently" with the -ly dropped off, but note that there are also formations like think fruit or think pink, and "think different" could belong to that group. In other words "What should I think about this product?" "Think (that it is) different".
Anyway, "think differently" is a terrible slogan.
One possibility we're forgetting here is the that the adjective may be a substantive adjective. Substantive adjectives are adjectives which are used alone without the noun they are describing. For example, good, bad, and ugly in this sentence, 'The good, the bad, and the ugly, which is really, 'The good people, the bad people, and the ugly people.'
In this case, Apple's slogan, 'Think different', would be read 'Think different things', and is thus a perfectly grammatical.
Apple did not mean "think differently". That is, they are not suggesting that you think in a different way. They really meant "think different", that is, rather than thinking about the things you usually think about, think about things that are different.
An analogous slogan might be, "Thinking about your opportunities as a high school graduate? Think college."
If the message is taken to mean:
Then it could be grammatically incorrect. Just not sure I can say this is "punctuationally" correct, but from a logo/branding/marketing point of view the use of punctuation may take something away from the impact of the message even if making the intention of the message unclear.