The idea of the meme is getting more and more topical, so not being scientist, I wrote how I understand it.
All memes are produced by combination of creativity and knowledge. For meme to survive in a particular persons mind it takes to be enough important. The value of memes importance is the sum of its explanational and inspirational values. All memes can be inspirational or explanational or both, depending on weather they are more inspirational or explanational. For instance scientific memes are more explanational when poetry and music is more likely inspirational. Similar memes are in competition with each other. Similar memes I call memes that covers the same object. Stronger memes are those which sum of explanational and inspirational values are higher. For example if one meme explains something by 23 and it doesn't have anything that inspires, this meme will loose to a similar meme that maybe doesn't explains by 6 but it by 21, because 23 (explanation) + 0 (inspiration) = 23 (importance), but 6 + 21 = 26, second meme has more chances to survive as it appears to be more important. For example bright object in dark sky’s can be explained by a helicopter, but some will find it to be more inspirational if it was UFO. These values ar not absolute measurable numbers, they can variate in time and in different minds having a particular copy of meme, these values can be very different. However groups of people can share similar importance of the same memes (interests, religion, job).
Meme consists of concepts and relations that binds them together. Both concept and relation can have their inspirational and explanational values. Some concepts are not inspirational at all but connection between has a high inspirational value. This phenomena appears when we say "it can't be a coincidence". Memes inspirational and explanational value is a sum of concepts and connections inspirational and explanational values.
Some memes are simple when some are very complicated. Complicated memes are made of simpler ones and these simpler memes fills some particular function to make meme more important. These meme systems can be competing or supporting to each other. Competition occurs when some objects are overlapped by incompatible memes. Minds that find a meme ore meme system important tends to support. There is a whole set of professions that are dedicated for supporting and vitalizing memes. In other words to increse their importance by making memes more inspirational or explanational or creating new memes for including in existing meme system to make it stronger. Some of these professions are scientists, philosophers, theologians and marketing specialists. Religion and art both creates inspirational memes, but religion connects them in a system when art creates separated memes that doesn't support each other. In fact in many cases they supports religious memes instead.
Memes themselves are not true or false, but they are based on more or less evidable objects. Memes that are based on evidence tends to be more explanational when other memes tends to cover the lack of evidence with inspiration.
I hope I have written something explanational and inspirational as well as given a little support to meme of the meme.