What 'miasma' refers to?
The passage below is from ‘the Blank Slate’ by Steven Pinker.
http://evolbiol.ru/blankslate/blankslate.htm Different cultures, then, don't come from different kinds of genes — Boas and his heirs were right about that — but they don't live in a separate world or stamp a shape onto formless minds either. The first step in connecting culture to the sciences of human nature is to recognize that culture, for all its importance, is not some miasma that seeps into people through their skin. Culture relies on neural circuitry that accomplishes the feat we call learning. Those circuits do not make us indiscriminate mimics but have to work in surprisingly subtle ways to make the transmission of culture possible.In this passage I cannot figure out the meaning of underlined 'miasma' in this context.
In Wikipedia, 'miasma' is "
a contagious power ... that has an independent life of its own. Until purged by the sacrificial death of the wrongdoer, society would be chronically infected by catastrophe."
The word has a negative connotation in Wikipedia's description, but does not have any in this context in question.
I know my question is not well-posed and specific.
But I wish to know why Steven Pinker used this word in this context.
Hope for your replies.
Regards.