Continual - continuous

When I was at school (writes Peter Wilson), an English teacher used to insist on the correct use of these words. I could not fully understand the distinction then, and the more I see them used in print now, the less am I sure that anyone does. This may be a shame.

It reduces the precision of the English language if a useful distinction ceases to exist; and the mere fact that many people use the words continual and continuous to mean the same thing does not make it correct to do so. More convincing evidence may be found in the fact that the experts themselves are not clear.

• The on-line Fowler says: "Continual is the older word (14c), and once had all the meanings it now (since the mid-19c) shares with continuous (17c)."
• OED includes in its definition of continual "continuous (in time); or less strictly, repeated with brief intermissions, very frequent." So the two words are so close that they can be defined in terms of each other.

There was a distinction, and pedantic teachers may still insist upon it. So you should be aware of it. Here are two explanations. The first was given by the original Fowler in 1926.

• "That is -al which either is always going on or occurs at short intervals and never comes (or is regarded as never coming) to an end. That is -ous in which no break occurs between the beginning and the (not necessarily or even presumably long-deferred) end."

• Burchfield says, in his (3rd) edition of Fowler that the original advice is "somewhat cryptic", adding examples to show "how difficult it is to keep the two meanings apart". I find it hard to draw a firm line between them by means of Fowler's definition. Burchfield continues, in a more scholarly and less prescriptive way, "Only since the mid-19c. has it been customary to regard continual as being applicable to events that occur frequently but with intervals between, and continuous to anything that proceeds in an unbroken or continuous manner. In practice, the distinction is not as neat as that."

For AWE, the most telling sentence is "In practice, the distinction is not as neat as that." The best practical advice that we can give, if your use of either continual or continuous is questioned, is to drop the word. Find some other way to say what you mean. Burchfield suggests

• For 'continual, 'recurrent' or 'intermittent'
• For 'continuous 'uninterrupted', 'unbroken' and 'incessant'.

See also More on Continual - continuous