Frederic W. Farrar (1831-1903), History of Interpretation: Eight Lectures Preached Before the University of Oxford
(London: Macmillan and Co., 1886), p. 19 (discussing Hillel's seven rules):
The second, the rule of "equivalence," infers a relation between two subjects from the occurrence of identical expressions.
Id., pp. 21-22:
This rule of "equivalence" has always been prevalent in scholastic systems. It means the isolation of phrases, the misapplication of parallel passages, the false emphasising of accidental words, the total neglect of the context, "the ever-widening spiral ergo from the narrow aperture of single texts." It is just as prominent, and quite as mischievous, in Hilary and Augustine, in Albert and Aquinas, in Gerhard and Calovius, as in Hillel or Ishmael.
For the quotation, see Samuel Taylor Coleridge (1772-1834), Aids to Reflection in the Formation of a Manly Character
(London: Taylor and Hessey, 1825), p. 357:
I have, I confess, no eye for these smoke-like Wreaths of Inference, this ever-widening spiral Ergo from the narrow aperture of perhaps a single Text: or rather an interpretation forced into it by construing an idiomatic phrase in an artless Narrative with the same absoluteness, as if it had formed part of a mathematical problem!