If the combat is to be regarded as not yet ended, then the new contest which is opened by the arrival of assistance fuses into the former; therefore they flow together into one common result, and the first disadvantage vanishes completely out of the calculation.  But this is not the case if the combat was already decided; then there are two results separate from each other.  Now if the assistance which arrives is only of a relative strength, that is, if it is not in itself alone a match for the enemy, then a favourable result is hardly to be expected from this second combat:  but if it is so strong that it can undertake the second combat without regard to the first, then it may be able by a favourable issue to compensate or even overbalance the first combat, but never to make it disappear altogether from the account.

At the battle of Kunersdorf,(*) Frederick the Great at the first onset carried the left of the Russian position, and took seventy pieces of artillery; at the end of the battle both were lost again, and the whole result of the first combat was wiped out of the account.  Had it been possible to stop at the first success, and to put off the second part of the battle to the coming day, then, even if the King had lost it, the advantages of the first would always have been a set off to the second.

     (*) August 12, 1759.

But when a battle proceeding disadvantageously is arrested and turned before its conclusion, its minus result on our side not only disappears from the account, but also becomes the foundation of a greater victory.  If, for instance, we picture to ourselves exactly the tactical course of the battle, we may easily see that until it is finally concluded all successes in partial combats are only decisions in suspense, which by the capital decision may not only be destroyed, but changed into the opposite.  The more our forces have suffered, the more the enemy will have expended on his side; the greater, therefore, will be the crisis for the enemy, and the more the superiority of our fresh troops will tell.  If now the total result turns in our favour, if we wrest from the enemy the field of battle and recover all the trophies again, then all the forces which he has sacrificed in obtaining them become sheer gain for us, and our former defeat becomes a stepping-stone to a greater triumph.  The most brilliant feats which with victory the enemy would have so highly prized that the loss of forces which they cost would have been disregarded, leave nothing now behind but regret at the sacrifice entailed.  Such is the alteration which the magic of victory and the curse of defeat produces in the specific weight of the same elements.

Therefore, even if we are decidedly superior in strength, and are able to repay the enemy his victory by a greater still, it is always better to forestall the conclusion of a disadvantageous combat, if it is of proportionate importance, so as to turn its course rather than to deliver a second battle.