It would be easy to reduce these five to three, and range all considerations under Economy, Climax, and Variety; or we might amplify the divisions; but there are reasons of convenience as well as symmetry which give a preference to the five.  I had arranged them thus for convenience some years ago, and I now find they express the equivalence of the two great factors of Style—–­Intelligence and Sensibility.  Two out of the five, Economy and Simplicity, more specially derive their significance from intellectual needs; another two, Climax and Variety, from emotional needs; and between these is the Law of Sequence, which is intermediate in its nature, and may be claimed with equal justice by both.  The laws of force and the laws of pleasure can only be provisionally isolated in our inquiry; in style they are blended.  The following brief estimate of each considers it as an isolated principle undetermined by any other.

1.  The law of economy.

Our inquiry is scientific, not empirical; it therefore seeks the psychological basis for every law, endeavouring to ascertain what condition of a reader’s receptivity determines the law.  Fortunately for us, in the case of the first and most important law the psychological basis is extremely simple, and may be easily appreciated by a reference to its analogue in Mechanics.

What is the first object of a machine?  Effective work—­Vis Viva.  Every means by which friction can be reduced, and the force thus economised be rendered available, necessarily solicits the constructor’s care.  He seeks as far as possible to liberate the motion which is absorbed in the working of the machine, and to use it as Vis Viva.  He knows that every superfluous detail, every retarding influence, is at the cost of so much power, and is a mechanical defect though it may perhaps be an aesthetic beauty or a practical convenience.  He may retain it because of the beauty, because of the convenience, but he knows the price of effective power at which it is obtained.

And thus it stands with Style.  The first object of a writer is effective expression, the power of communicating distinct thoughts and emotional suggestions.  He has to overcome the friction of ignorance and pre-occupation.  He has to arrest a wandering attention, and to clear away the misconceptions which cling around verbal symbols.  Words are not llke iron and wood, coal and water, invariable in their properties, calculable in their effects.  They are mutable in their powers, deriving force and subtle variations of force from very trifling changes of position; colouring and coloured by the words which precede and succeed; significant or insignificant from the powers of rhythm and cadence.  It is the writer’s art so to arrange words that they shall suffer the least possible retardation from the inevitable friction of the reader’s mind.  The analogy of a machine is perfect.  In both cases