As the previous article showed, Jones’s argument carried both a strength and a weakness at once. The conclusion — “not accident, not borrowing” — rests on independently checkable evidence. But the question that mattered most, which sound actually corresponds to which, he never answered. Filling that gap fell, after his death, to the next generation of European scholars.
Three people who filled the gap
Franz Bopp (1791–1867, Germany) published, in 1816, while still in his twenties, “On the Conjugation System of the Sanskrit Language, in Comparison with that of Greek, Latin, Persian, and the Germanic Languages.” Here, for the first time, the intuition Jones had packed into a single paragraph was cast into a systematic comparative table of verb conjugation across five languages. Not a casual resemblance between individual words, but patterns of inflection checked one against another, line by line — Bopp put on paper exactly what Jones meant when he said “no philologer” could fail to be convinced.
Rasmus Rask (1787–1832, Denmark) went a step further in 1818, in a prize essay investigating the origin of Icelandic (Old Norse). He was the first to show that Germanic consonants diverge from their counterparts in other Indo-European languages with a definite regularity. Latin p, for instance, consistently corresponds to Germanic f (pater → father). This wasn’t scattered coincidence — it was a shift predictable as a pattern.
Jacob Grimm (1785–1863, Germany), in the revised second edition of his Deutsche Grammatik (1822; first published 1819), organizes Rask’s observation and formalizes it into a systematic phonological law — what would later be called “Grimm’s Law.” It shows that specific consonants in Proto-Indo-European shift in predictable ways in the Germanic branch. Grimm himself is covered in full in this site’s Jacob Grimm feature.
What it means to become a “law”
This is the decisive turn. Jones’s “too close to be an accident” was a judgment built on impression. Grimm’s Law is different — it predicts, in advance, which sound corresponds to which. The form a word should take in the Germanic branch could now be derived mechanically from its Latin or Greek counterpart. Predictable, and falsifiable if the prediction fails — in this sense, comparative linguistics only now became a discipline with a genuinely testable “law.” The intuition Jones expressed as “no philologer could fail to be convinced” has, by this point, transformed from a personal conviction into a procedure anyone can apply.
Light and shadow — a second current from the same discovery
This development wasn’t an unambiguous story of progress. In nineteenth-century Europe, the linguistic discovery of an “Indo-European” family got tangled up, almost imperceptibly, with the story of an “Aryan race” — a racial narrative that was, in fact, baseless. That speakers of a common ancestral language once existed is a claim linguistics can support. That those speakers formed a single “people,” and a civilizationally superior one at that, was a leap imported from entirely outside linguistics. How this conflation spread, and what harm it did, is covered in more depth in this site’s Max Müller feature. In fairness to Jones, it’s worth adding here that nothing in this discourse itself equates race with language.
Summary
| Figure | Year | Contribution |
|---|---|---|
| William Jones | 1786 | Points out the resemblance among Sanskrit, Greek, and Latin; states the intuition of a common ancestor |
| Franz Bopp | 1816 | Systematically compares verb conjugation across five languages, backing the intuition with a comparative table |
| Rasmus Rask | 1818 | Discovers that Germanic consonants shift with regularity |
| Jacob Grimm | 1822 | Formalizes that regularity as “Grimm’s Law” |
In a nutshell — one judge’s intuition could never have become a discipline on its own. Over thirty-some years, European scholars forged it, step by step, into a comparative table, then a discovered regularity, then a predictive law. What this feature has traced is the story of a single discovery — and, at the same time, the story of how one act of conviction grows into a verifiable field of study.