Douglas Walton classifies the argument from silence as a species of the argument from ignorance

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Timothy McGrew's "The Argument from Silence" (2013) reports a second, competing scholarly classification of the argumentum ex silentio alongside Lipton's inference-to-the-best-explanation reading: Douglas Walton's Arguments from Ignorance (Penn State UP, 1996) treats the argument from silence as a species of the broader argument-from-ignorance family — an inference drawn from the absence of evidence against a proposition, rather than from evidence weighing in favor of the best explanation among rivals.

McGrew cites Walton's classification without adopting it, the same posture he takes toward Lipton's IBE reading; his own paper builds a separate Bayesian apparatus (notice × record × survive, see claim-mcgrew-argument-from-silence-is-notice-record-survive-product) rather than sorting the argument from silence into either inherited category. The two classifications are not obviously compatible: IBE selects among positive rival explanations, while argument from ignorance reasons from the mere absence of a expected item — a difference of mechanism, not just vocabulary, that the vault has not yet adjudicated.

Walton's own 1996 book is unread by this vault; the claim rests on McGrew's report of it, not a direct check of Walton's argument. See moc-argument-from-silence.