Dr. Boenninghausen about time modalities in homeopathy...
" But of the greater importance are the aggravations and alleviations at particular times of the day, and this with respect to those which refer to single symptoms as well as those that refer to the general health.
In this respect Homoeopathy possesses a great and valuable treasury of well proven experiences which are being more and more enlarged by careful observations.
For there is hardly any disease, from the malignant internal fevers down to local ailments, in which during the different times of the day there does not manifest itself a more or less decided and distinct aggravation or alleviation.
Now since homoeopaths have learned these peculiarities also in the various medicines during their provings on healthy persons, they are enabled to make extensive and blessed use of this peculiarity in their therapeutics, and they are obliged to do this in order that they may satisfy the rule Similia Similibus also in this respect."