Thornton opens his 1873 volume with a borrowed voice: the preface is presented as a found text, pieced together from fragments supplied by a frequent 'companion of my solitude.' This framing device immediately establishes a dialogic, almost theatrical tone, as the speaker rails against a world 'richer than usual in Truths grown obsolete.' The epigraph from Berkeley's Hylas and Philonous signals a revolt from 'metaphysical notions to the plain dictates of nature and common sense,' a movement Thornton will trace through his critique of Humean skepticism and utilitarian ethics.

A Preface Borrowed and Pieced

The preface is not a conventional authorial introduction but a collage of quotations, presented as if discovered in fragments and needing only 'a little piecing' to become presentable. The voice that emerges is distinctly Carlylean: it speaks of 'gospel tidings burning until it be uttered,' of a 'Logic-mill' that grinds out virtue from 'the husks of Pleasure,' and of offering 'sweet incense to the Devil' with a frying-pan as censer. This rhetorical strategy allows Thornton to adopt a prophetic, indignant tone without claiming it as his own—he is the editor of a found manifesto, not its sole author. The effect is to distance himself from the very passion he channels, creating a layered authorial persona that is both engaged and ironic.

Hume as Huntsman and Riddler

Thornton's treatment of David Hume is the book's most sustained critical passage. He praises Hume's 'golden rules of philosophical research'—the testing of ideas by experience and the rejection of unverifiable speculation—but condemns his method as sport rather than inquiry. Hume, he writes, 'put time-honoured commonplaces on the rack' and passed 'summary sentence of extinction' on those that failed to justify themselves. Yet Thornton accuses him of enjoying the chase too much: like a huntsman who 'outrace his quarry' or starts a fresh hare to prolong the sport, Hume would follow any new negation rather than gather up verified affirmations. The metaphor is precise and damning: philosophy becomes a game, and ordinary people are the casualties, bewildered by 'vain and profane babblings' that lead no whither.

The Utilitarian's Self-Condemnation

Thornton's most pointed charge is that Hume, as a Utilitarian, 'stands self-condemned for making ordinary people uncomfortable.' The accusation hinges on utility: if the measure of action is its tendency to promote happiness, then a philosophy that unsettles faith and offers no stable ground fails its own test. Thornton quotes Hume's own reassurance—'Nature is always too strong for principles'—as a poor excuse for 'wanton tampering with other people's creeds.' The critique is not merely logical but moral: the philosopher who delights in riddles while exhorting others not to let doubt affect their actions is, in Thornton's view, irresponsible. The passage reveals the book's central tension: a defence of common-sense metaphysics that is itself deeply engaged with the very skepticism it opposes.

Berkeley's Revolt as Guiding Motif

The epigraph from Berkeley's Hylas and Philonous is not decorative but structural. Berkeley's speaker declares he has 'quitted several of the sublime notions' of the schools 'for vulgar opinions,' finding his understanding 'strangely enlightened' by the revolt from metaphysical subtleties to common sense. Thornton's project mirrors this movement: he seeks to redeem 'Truth from premature obsolescence' by reasserting the value of 'old-fashioned' ethical and metaphysical commitments against the corrosive doubts of modern philosophy. Yet the book does not simply reject skepticism; it engages it on its own terms, using Hume's own methods to expose the limits of a purely critical philosophy. The result is a work that is both a defence and a demonstration of the common-sense tradition.

Thornton's book is best approached as a series of linked essays rather than a systematic treatise. The reader should attend to the shifts in voice—from the borrowed Carlylean preface to the measured critique of Hume—and to the recurring tension between the desire for stable moral truth and the recognition that such truth must be defended against its most sophisticated opponents. The epigraph from Berkeley is a reliable guide: Thornton is, throughout, a philosopher who has revolted from 'sublime notions' to 'vulgar opinions,' but who knows that the revolt must be argued, not merely asserted.