There was once a time, as far as classical music is concerned, where form was the be all and end all. This can be traced back to the early dance forms such as the gigue (or jig) and gavotte. Later forms developed – in particular the sonata, which arguably found its ultimate expression in the Viennese symphonies of the Classical era. Nowadays, symphonies are still being written, but in name only. The same is true of poetry; sonnets and sestinas are not the norm. Indeed, the only form that seems to have survived is the Japanese haiku. And, perhaps, the Irish limerick.

How, now, are we to define poetry if it is not verse per se? Form was basically a matter of deciding how many metres were to be in each line and on what lines the rhymes were to fall. (Sonnets, for example, had fourteen lines and tolerated a variety of rhyme schemes.) Iambs and trochees have not gone away, nor have personification and onomatopoeia. When one poem works, do we understand why it reads better than another? Is it fluke or could it be the use – albeit unintentional – of some age old technique?

In 1913 a group of poets got together and laid down a number of determining factors they felt should guide their writing: they came to be known as the Imagists, led by a young Ezra Pound. This Anglo-American movement reacted against Victorian sentimentalism. They advocated the use of free verse (though they did not insist upon its use), common speech patterns, and clear concrete images. Their particular aspirations are, perhaps, best expressed in their own words:

1. To use the language of common speech, but to employ always the exact word, not the merely decorative word.

2. To create new rythmns – as the expression of new moods. We do not insist upon "Free-verse" as the only method of writing poetry. We do believe that the individuality of a poet may often be better expressed in free verse than in conventional forms.

3. To allow absolute freedom in the choice of subject.

4. To present an image. We are not a school of painters, but we believe that poetry should render particulars exactly and not deal with vague generalities.

5. To produce poetry that is hard and clear, never blurred or indefinite.

6. Finally, most of us believe that concentration is the very essence of poetry.

Most of these guiding principles – for want of a better expression – are alive and well in modern poetry. The most common means used to attain them is metaphor (and, in a similar vein, simile). These devices are the poetry of the man in the street, as much as euphemism and double entendre. The meaning of a word is never a simple thing but a complex web of associations. The poet must exploit these words, to get them to release their psychological energy. Poetry is analogous to chemistry, combining certain elements in a specific sequence to produce a desired effect. And sometimes it blows up in our faces!

I am not suggesting that the Imagist's manifesto contains the perfect distillation of what poetry is or could aspire to. There are noteworthy ideals expressed in the writings of other schools of thought, including symbolists, who sought to convey impressions by suggestion rather than by direct statement, and naturalists, like Zola, who theorised that writers should observe and record dispassionately; almost scientifically.

Achieving our artistic ambitions is often difficult. It's human to see more than clouds when we look up into the sky, and the ink blots aren't always butterflies, are they?

Poetry is, by the nature of its creation, a uniquely subjective medium. It is dependent, to a far greater degree than prose, on a contribution from our readers. As a young poet, I would become outraged if someone failed to "get" my poetry; the flaw, of course, could not be mine. I was short-sighted thinking I was capable of condensing everything I wanted to say into the few words I allowed myself, let alone expecting my readers to undo the puzzle in the right order.

Over the years I have been pleased to find that people were being reached - and on occasion quite deeply – but not in ways I had intended nor expected. There was something going on here and I wasn't in control. What I came to discover was that poetry can become the possession of the reader, when he or she imbues the words with a sense of self. Music can do this, as can art.

Let's return to chemistry for a moment. Many perfumes react differently depending on the type of skin to which they are applied. Sometimes our poems will make our readers feel wonderful; other times there's likely to cause an allergic reaction.

If the Imagist's reaction was against the formalistic poetry of their day, is all form necessarily bad?

The answer has to be, "No." What we fear is conforming, losing our poetic identity. Rhyme, half-rhyme, metre and meaning are only some of the possible elements in a verbal pattern. They can work for us or against us.

But if we are not conforming, to what extent are we still informing? And if so, on what levels? It's necessary to charge every word we write with as much poetic potential as possible so that it appeals concurrently to all levels of evocation and interpretation. "I love you," is just about the most powerful statement that can be uttered but it can be rendered impotent if it's framed in the wrong setting.

It is far too easy to dismiss the poetry that has gone before us as all technique and no soul, and act with some sort of superior air as if, free verse, is the ultimate expression of the poet's art. It may well prove to be (and that responsibility lies with us) but contained within the abstract there are inevitably little blocks of order, an allusion, a pun, a use of syncopated rhythm, metonymy, anaphora, hyperbole: these are the tools of our trade (and there are so many more with wonderfully archaic names). Don't dismiss them too readily. Look them up. Try them out. Find more.

If poetry is, as I believe and practice, a concentration of language, squeezed till the last drop of meaning is taken from it, then we cannot afford to become blasé, flippant, or over-confident. Words are our chosen weapons, but they can be turned on us if we don't handle them with care. A little technique can go a long way.