How do textual critics test a proposed conjectural emendation?

In textual criticism, a proposed conjectural emendation is tested using the same criteria applied when choosing between variant readings. This process is fundamentally an exercise in balancing probabilities, which are historical in nature.1

Critics evaluate emendations by considering two primary types of probability:

• Intrinsic probability: This assesses the likelihood of the reading based on the author's style, context, and the internal logic of the text.
• Transcriptional (paleographical or bibliographical) probability: This examines whether the proposed change is consistent with the types of errors likely to occur during the specific medium and period of the text's transmission (e.g., errors made by a tired copyist or those contingent on the printing process).1

The importance assigned to transcriptional probability depends on the historical circumstances of the text. If the transmitted text is close to the original, a conjecture that violates transcriptional probability is less likely to be correct. If the text has undergone a long, complex history of deterioration, the critic may place less weight on transcriptional probability. Ultimately, the critic must discriminate between readings, guided by the principle that the better reading is to be preferred (melior lectio potior).1