I.e. "from a rule without exception." Short for a dicto simpliciter, the a is often dropped because it is confused with the English indefinite article. A dicto simpliciter occurs when an acceptable exception is ignored or eliminated. For example, the appropriateness of using opiates is contingent on suffering extreme pain. To justify the recreational use of opiates by referring to a cancer patient or to justify arresting said patient by comparing him to the recreational user would be a dicto simpliciter.
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