Sec. 63. Thus we see that the phenomena of Climax, Antithesis, and Anticlimax, alike result from this general principle. Improbable as these momentary variations in susceptibility may seem, we cannot doubt their occurrence when we contemplate the analogous variations in the susceptibility of the senses. Referring once more to phenomena of vision, every one knows that a patch of black on a white ground looks blacker, and a patch of white on a black ground looks whiter, than elsewhere. As the blackness and the whiteness must really be the same, the only assignable cause for this is a difference in their actions upon us, dependent upon the different states of our faculties. It is simply a visual antithesis. iii. Need of Variety. Sec. 64. But this extension of the general principle of economy--this further condition to effective composition, that the sensitiveness of the faculties must be continuously husbanded--includes much more than has been yet hinted. It implies not only that certain arrangements and certain juxtapositions of connected ideas are best; but that some modes of dividing and presenting a subject will be more striking than others; and that, too, irrespective of its logical cohesion. It shows why we must progress from the less interesting to the more interesting; and why not only the composition as a whole, but each of its successive portions, should tend towards a climax. At the same time, it forbids long continuity of the same kind of thought, or repeated production of like effects. It warns us against the error committed both by Pope in his poems and by Bacon in his essays--the error, namely, of constantly employing forcible forms of expression: and it points out that as the easiest posture by and by becomes fatiguing, and is with pleasure exchanged for one less easy, so, the most perfectly-constructed sentences will soon weary, and relief will be given by using those of an inferior kind. Sec. 65. Further, we may infer from it not only that we should avoid generally combining our words in one manner, however good, or working out our figures and illustrations in one way, however telling; but that we should avoid anything like uniform adherence, even to the wider conditions of effect. We should not make every section of our subject progress in interest; we should not always rise to a climax. As we saw that, in single sentences, it is but rarely allowable to fulfill all the conditions to strength; so, in the larger sections of a composition we must not often conform entirely to the law indicated. We must subordinate the component effect to the total effect.