a priori

A priori refers to an assertion based on prior knowledge or intuition. In Latin, the term literally means “ from what is earlier .” An a priori determination is formed before investigation. For example, assuming that the road will be wet when it stops raining a minute before would be a priori reasoning.

A priori is the opposite of a posteriori , or after-the-fact knowledge.

For example:

In McCulloch v. Maryland , the Court questioned, “How will [it] ascertain, a priori, that a given amount of tax will crush the bank?”
- In other words, the Court was asking how they would know that the tax amount would crush the bank BEFORE it actually happens.
In Burch v. Louisiana , the Court held that it “[did] not pretend the ability to discern a priori a bright line below which the number of jurors participating in the trial or in the verdict would not permit the jury to function in the manner required by [their] prior cases.”

[Last reviewed in November of 2024 by the Wex Definitions Team ]

Keywords

Latin terms

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