It has the function, in other words, of negating its own meaning in another semiotic system, in this case the semiotic system of the stoplight.

也就是说，他有这样那样的功能，在不同语义系统中表示的甚至完全相反，就像红灯表示的这些不同含义一样。

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In other words, they probably bear a distant relation to the semiotics of the stoplight, and that's probably why red was chosen for ambulances and police cars: because they put into your head the notion of "stop."

这很可能是源自于,红灯在一些语义中表示停止的意思，它被应用在了救护车和警车上：,因为他们带有警告的意味“

耶鲁公开课 - 文学理论导论课程节选

As I say, there's a certain instability which could never apply in the semiotics of the stoplight because there it's not so much a question of but rather the insistence that the color is just that color.

我承认，颜色的选择有时候是有规律的,但是在语义学上这解释不通,因为他们不考虑,但是语义学家认为颜色只单纯表示颜色。

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