It’s easy to confuse the words prescriptive and proscriptive. The odd thing is that they are just the opposite of each other.
If there is a way of overcoming something, such as a writer’s block, or an inability to get the answer to a difficult question, someone may suggest a way that will help you achieve that solution. That is, they may prescribe something, such as a doctor may prescribe a medication to overcome an illness.
But to proscribe something, or make it proscriptive means to deny it, or prohibit it. If, for instance, the solution to overcoming an illness is by ingesting a medication that is not approved by the FDA, the medication has been proscribed. In recent weeks we have heard the President say that, while the use of torture may produce an answer not otherwise attainable, the use of torture is proscribed. (i.e., it is forbidden)
The word proscribed comes to us from an origin in Latin, prōscrībere… to publish in writing, confiscate, or outlaw. As you can see from the root word, scribe, meaning to write, the addition of the prefix “pro” makes it into a word which means to “write against.” It’s not difficult, therefore, to see the current American English meaning as being a direct translation from its Latin origin.
To be proscriptive is to act to make something forbidden. Parents proscribe activities by their children on a regular basis. The method of doing so determines whether the proscription will be well received and abided by, however. A direct “You cannot go to the drive-in movie with him ” stands a good chance of being ignored, in that teenagers relish the opportunity to strike out on their own in such a situation. But a more gentle “We really don’t feel comfortable with you and John going to the drive-in tonite until we have a chance to talk about this further” may receive a more positive response, as it appeals to the teen making a choice which may have a better future than the risk of going anyway.
For the most part, however, proscriptions have more to do with societal norms rather than personal or individual rules of behavior.
Social norms are rules or customs that regulate the behavior of individuals in a society. Governments do not officially enforce norms, though they may encourage or discourage them, and some norms are eventually made into laws. Norms generally constrain behavior and are often seen as performing certain functions in a culture or community. For example, talking loudly on your mobile phone in public is discouraged because being quiet in public areas allows others to enjoy themselves and continue in peace.” (ehow.com)
It is hard for some people to accept such norms. In rebellion against “the norm of society” someone may choose to violate the norm intentionally. As said above, that doesn’t necessarily call for legal action. But the individual may find that enacting a proscribed behavior isolates them and helps to develop a reputation which is negative and unpopular.