is composed of a great number of independent statements, any one of which may be intentionally or unintentionally false, while the others are bonâ fide and accurate, or conversely, since each statement is the outcome of a mental operation which may have been incorrectly performed, while others were performed correctly. It is not, therefore, enough to examine a document as a whole; each of the statements in it must be examined separately; criticism is impossible without analysis.
Thus internal criticism conducts us to two general rules.
(1) A scientific truth is not established by testimony. In order to affirm a proposition we must have special reasons for believing it true. It may happen in certain cases that an author's statement is a sufficient reason for belief; but we cannot know that beforehand. The rule, then, will be to examine each separate statement in order to make sure whether it is of a nature to constitute a sufficient reason for belief.
(2) The criticism of a document is not to be performed en bloc. The rule will be to analyse the document into its elements, in order to isolate the different statements of which it is composed and to examine each of them separately. Sometimes a single sentence contains several statements; they must be separated and criticised one by one. In a sale, for example, we distinguish the date, the place, the vendor, the purchaser, the object, the price, and each one of the conditions.
In practice, criticism and analysis are performed simultaneously, and, except in the case of texts in a difficult language, may proceed pari passu with interpretative analysis and criticism. As soon as we understand a phrase we analyse it and criticise