A Handbook of the English Language
Chapter 123
ON WHEN, THEN, AND THAN.
§ 388. The Anglo-Saxon adverbs are _whenne_ and _þenne_ = _when_, _then_.
The masculine accusative cases of the relative and demonstrative pronoun are _hwæne_ (_hwone_) and _þæne_ (_þone_).
Notwithstanding the difference, the first form is a variety of the second; so that the adverbs _when_ and _then_ are really pronominal in origin.
§ 389. As to the word _than_, the conjunction of comparison, it is another form of _then_; the notions of _order_, _sequence_, and _comparison_ being allied.
_This is good_; _then_ (or _next in order_) _that is good_, is an expression sufficiently similar to _this is better than that_ to have given rise to it; and in Scotch and certain provincial dialects we actually find _than_ instead of _then_.
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