Paradigm, another fashionable term for what used to be called a "school". But I would like to know what valuable new perspective I would get out of calling an idea a meme.
For the same reason you wouldn't just refer to a gene as 'a nucelotide sequence'. With the term gene comes a sense of behaviours and interactions that is not present in the term 'nucleotide sequence', just as meme refers to more than just an idea.
The evolutionary stresses which can influence the changes, proliferation or extinction of a single idea throughout a community is connoted in the term meme, where an idea implies simply a concept created by a single entity. The term draws parallels between evolving systems which encourages us to explore how we can use, say, genetics to better understand the evolution of a culturally learned unit.
Language can be problematic if jargon terms are used to isolate other parties or no longer mean what they are supposed to. But coining a new term to better define a concept can often be useful if that concept has connotations that didn't exist before.
Athon