# The scientist as sentimentalist: a Humean argument turned against scientific certainty

Commentary on Orthodoxy by G. K. Chesterton.

On [CH04.P012](https://glosses.org/orthodoxy/pg16769-r1/CH04.P012/#char=504,606): "He is a sentimentalist in this essential sense, that he is soaked and swept away by mere associations."

The accusation concerns the source of a conviction: repeated experience produces an expectation so powerful that it feels like a logical bond. This is a close philosophical parallel to Hume, rather than evidence here of a documented borrowing. In *An Enquiry concerning Human Understanding* (first published in 1748), Hume distinguishes demonstrable relations of ideas from matters of fact, whose opposites remain conceivable. His analysis of familiar causal sequences explains how habit can conceal the fact that their effects could never have been discovered by thought alone. See [section IV, paragraphs 1–2 and 6–11](https://davidhume.org/texts/e/4), in Peter Millican's online text following the 1777 edition.

Chesterton makes this analysis polemical by comparing causal expectation with a lover's emotional association. But Hume's conclusion also qualifies the insult: custom makes experience usable and practical action possible; it is not simply a regrettable weakness of professors. [Section V, paragraphs 4–6](https://davidhume.org/texts/e/5), identifies habit as the indispensable basis of these expectations.

The distinction is therefore between an empirical connection and a connection demonstrable from the ideas alone. Chesterton's phrase ‘no connection’ is defensible in the latter sense, which his opening emphasis on a *logical* connection supplies. Taken to deny every evidential difference between tides and lost love, it would outrun the argument. Showing that an apple tree with tulips is imaginable does not itself show that the expectation of apples is foolish. Fairyland supplies a test of logical possibility; further argument is needed to assess the strength of an empirical explanation.

## Sources

- [David Hume, An Enquiry concerning Human Understanding, section IV](https://davidhume.org/texts/e/4), E 4.1–2, 4.6–11; SBN 25–30; Peter Millican online edition, 1777 copytext
- [David Hume, An Enquiry concerning Human Understanding, section V](https://davidhume.org/texts/e/5), E 5.4–6; SBN 42–45; Peter Millican online edition, 1777 copytext
- [Peter Millican, Editorial Notes to the First Enquiry](https://davidhume.org/texts/e/notes), Publication history and concluding description of the 1777 text followed

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