What I'm calling critical thinking textbooks were referred to at the time either as textbooks on philosophical rhetoric or as logic texts, where the logic was of the sort that would be eclipsed by the new formal logic. Much of the subject matter of these old texts (fallacies, Mill's methods, etc.) is now generally presented to students in critical thinking courses.
One difference between these old textbooks and today's post-secondary, critical thinking texts is that the latter volumes seldom include material about a fact-opinion distinction. Why? I conjecture that the change is due, in part at least, to shifts in the meanings of the key terms.
I've posted some notes on an older interpretation of 'fact', on which only particular, observable occurrences (or conditions) were said to be facts. General laws of nature, mathematical truths, etc. weren't. This older reading of 'fact' was evident in some of the textbook passages quoted in my last post. It's even more in evidence in John Grier Hibben's 1905 textbook, when Hibben calls
attention to the difference between the terms, a 'truth' and a 'fact'. A fact carries with it only the special and individual character of the particular occurrence in which it is manifested. A truth, however, is always universal in its very nature, admitting of universal application, and capable of illustration in an indefinite number of different facts which embody its essence. (Hibben, Logic: Deductive and Inductive [1905], pp. 171-2)Clearly, Hibben (who went on to become President of Princeton University) did not equate facts with truths, not even with objective truths.
It's interesting, though, that back in 1849, George Cornewall Lewis acknowledged another reading of 'fact', one that sounds more modern. Recall what Lewis wrote:
A fact, as so defined, must be limited to individual sensible objects, and not extended to general expressions or formulas, descriptive of classes of facts, or sequences of phenomena, such as that the blood circulates, the sun attracts the planets, and the like. Propositions of this sort, though descriptive of realities, and therefore, in one sense, of matters of fact, relate to large classes of phenomena, which cannot be grasped by a single sensation, which can only be determined by a long series of observations, and are established by a process of intricate reasoning. (Lewis, 'Essay on the Influence of Authority in Matters of Opinion', 1849, pp. 1-2 [Emphasis added])Lewis here allows for a broader reading of 'fact', one on which the term applies to any reality.
The ambiguity of 'fact' is explicitly noted by Father George Hayward Joyce, a Jesuit whose textbook, Principles of Logic, first appeared in 1908. He wrote:
The Fact is sometimes restricted to signify the particular concrete facts of experience. Sometimes it is extended to include whatever has been proved to be real, and in this sense can be used of a theory whose truth has been established. (Joyce, Principles of Logic, 2nd edition [1916; 1st ed. 1908], p. 362 [Emphasis in original])Perhaps, by the early 20th Century 'fact' was being used often in its more general, modern sense (at least in the UK and Ireland). Authors of textbooks (such as Hibben) may have been fighting a rear-guard battle, insisting on the word's older, proper use -- much as writers of critical thinking texts now insist on the old meaning of 'begging the question' even though that reading has largely been abandoned in the wider culture.
By the 1950s, philosophers seem to have given up and adopted the more popular interpretation of 'facts' as being equivalent in meaning to 'truths'. Some scientists, though, stuck to the old meaning of 'fact'. At least, such divergent uses are indicated by Henry Siggins Leonard in his 1957 text, Principles of reasoning: an introduction to logic, methodology, and the theory of signs. After defining 'facts' as true propositions (p. 47), Leonard adds that 'some scientists use the word "fact" in a somewhat narrower sense, perhaps to refer to those true propositions whose truth can be directly confirmed by observation.'(Leonard, Principles of reasoning [Dover, 1967, 1st published in 1957], p. 47, n. 3)
This state of play is partly confirmed by Stuart Chase in his Guide to Straight Thinking, with thirteen common fallacies (1956). When it comes to facts, says Chase, he'll rely on the definition adopted by scientists rather than that of the philosophers. His definition is as follows:
A fact is an event in space-time which remains the same from different viewpoints -- or, more technically, is invariant under a transformation of axes. In ordinary discussion a fact is invariant as seen by competent observers. (Chase, Guide to Straight Thinking [Phoenix House, 1959, 1st published in 1956 by Harper's], p. 47)This conception of facts preserves part of the old meaning by including in the category of facts all the objective, observable occurrences. It diverges from the old meaning by not explicitly requiring that all facts be observable (e.g., facts will include micro-events that are too small to be seen even via our best microscopes); and it diverges from the old reading by not including the inner mental events that can be detected by means of introspection.
So, again, the old fact-opinion distinction that was a mainstay in old critical-thinking textbooks relied on a different (and much narrower) understanding of 'fact', according to which the facts did not include all the objective truths. As a result, it was a very different distinction from the one that is so often conveyed today to high-school students.
In the next post in this series, I'll document changes in the use of 'opinion'.