Some affixes are used with great freedom. They are said to be productive. The suffix -ness can be added to a very large number of adjectives to form a noun: obvious, obviousness; friendly, friendliness; fruitful, fruitfulness; cheap, cheapness; and so on. In fact the speaker of English is fairly free to make up new nouns on this model, although he is likely to feel somewhat reluctant to do so if there is an already existing noun with the meaning he desires. For instance, gratefulness and legalness are likely to be thought rather odd words since they are trying to compete
with gratitude and legality. Nevertheless, the tendency to coin new words on the model ‘adjective+ -ness’ can be observed when people say things like sincereness, if they are not aware of the existence of the word sincerity or are unable to think of it on the occasion in question. The case is different with suffixes like the -th in warmth. There is only a handful of nouns formed on this pattern, and even some of these have stems that have become less recognizable in the course of history: width is based upon wide, length upon long, health upon a now obsolete forerunner of the word whole, in the sense ‘healthy’. In fact, the suffix -th is fossilized and almost totally unproductive. In between the two extremes of -ness and -th there are many gradations of productiveness (or is it productivity?). The suffix-ation is obviously less widely used than-ness, but more productive than -th. Think of words like hospitalization; most words that end in -ize seem to accept the further ending fairly readily. In general, derivation is a historical process that has resulted in the addition of words to the lexical stock of the language over the centuries. It is not indulged in with perfect freedom by the users of English. There are always greater restrictions on the production of new words than on the production of new sentences. Patterns of composition are also highly constrained. Breakfast, based upon break and fast is an unproductive model. We could not call a garage mechanic a mend-tyre. On the other hand, there are highly productive patterns for combining nouns with nouns to
form new nouns: key ring, key chain, key case, key wallet, doorknob, door handle, door hook, notepaper Since the structure of these expressions is compound, and the process of composition merely entails putting two stems together without modification, it is often not at all clear whether we should count such formations as one word or two. The reader might like to ask himself whether the following expressions are part of his own lexical stock, or whether the model on which they are constructed is so productive that he could interpret them and coin them at need: chair seat, conference programme, speech therapy, application form, job opportunity, camera shop, floor board, invitation date I assume that occasionally there will be some hesitation in answering the question. It appears that the contents of one’s lexical stock are in some respect indeterminate. It could very well be that the lexical stock and the formation rules for coining new expressions overlap. At all events, the indeterminacy does not affect the ‘output’ of the language user; he is equally intelligible whether he has ‘made it up’ or repeated it from memory, and we cannot tell which he has done. The interesting thing is that a compound expression of the kind camera shop, etc. can be incorporated into further layers of composition with results like the following: key ring wallet, door handle screws, car park attendant, insurance building car park, etc. This is so fruitful a way of coining new expressions that it is much used in technical vocabularies (e.g. litho-drawing ink, watercolour wash) and newspaper headlines (e.g. job loss
total, cabinet discussion leak).