Question: The thing is, I am confused whether the word *selfish* itself can be used without expressing a negative connotation. I am a bit biased about it since I believe that by using this word it automatically implies that a third party will be affected by the action. 

The thesaurus provides *self-interested*, *self-seeking*, *egoistic*; *illiberal*, *parsimonious*, and *stingy* as its synonyms; and I am aware that some can be used in a positive manner. For example self-seeking doesn't necessarily mean I am affecting someone else.

In other words, will everyone who hears *selfish* automatically perceive a negative meaning for the preceding action?

Could there be a better word that could express a similar meaning without being negative?

Answer: 
Self-preservation
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> Self-preservation is the first responsibility — *Margaret Anderson*
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**Ambition** is related and can be positive, but it's not quite the same thing, and in the wrong context it could be seen negatively.

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> [**ambition**](http://www.merriam-webster.com/dictionary/ambition) - an ardent desire for rank, fame, or power
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