a posteriori

[ ey po-steer-ee-awr-ahy, -ohr-ahy, -awr-ee, -ohr-ee ]

adjective

1. from particular instances to a general principle or law; based upon actual observation or upon experimental data: Compare a priori ( def 1 ).

   an a posteriori argument that derives the theory from the evidence.

2. not existing in the mind prior to or independent of experience. Compare a priori ( def 2 ).

a posteriori

/ ɑː; -rɪ; eɪ pɒsˌtɛrɪˈɔːraɪ /

adjective

1. relating to or involving inductive reasoning from particular facts or effects to a general principle
2. derived from or requiring evidence for its validation or support; empirical; open to revision
3. statistics See posterior probability

Word History and Origins

Origin of a posteriori¹

1615–25; < Latin: literally, from the one behind. See a- ⁴, posterior

Word History and Origins

Origin of a posteriori¹

C18: from Latin, literally: from the latter (that is, from effect to cause)

Example Sentences

In scholastic terms this was a debate over the reliability of a posteriori reasoning; in our terms it is a debate over the evidence of things, or over Evidence-Indices.

From Literature

This a posteriori saga gives us a refreshed Raphael, whose psychological acuity feels newly approachable.

From New York Times

“There’s no rigorous mathematical argument you can write about one event evaluated a posteriori,” he said.

From Fox News

The maximum a posteriori value and minimal 68.3% credible interval from this posterior density function is .

From Nature

Although this specific interaction was not quantified in this example, we view this a posteriori justification of a stereochemical outcome as a foundation for future rational design of such interactions in catalytic systems.

From Nature