 The suggestion here seems to be that the relative rotation in stage (i) of the experiment might immediately generate an outward force (before any rotation is communicated to the water), if the sides of the bucket were massive enough. (Note that this response could not have been made by Leibniz – even if he had wanted to defend Machian relationism – because it involves action at a distance between the water and the parts of the bucket, something he regarded as a metaphysical absurdity.)