>"It is indeed a matter of great difficulty to discover, and >effectually to distinguish, the true motion of particular bodies from >the apparent; because the parts of that immovable space, in which >those motions are performed, do by no means come under the observation >of our senses. [...] >But how we are to collect the true motions from their causes, effects, >and apparent differences; and, vice versa, how from the motions, >either true or apparent, we may come to the knowledge of their causes >and effects, shall be explained more at large in the following tract. >For to this end it was that I composed it."
It's not completely clear what he means by "true motions" and "apparent motions", but if he meant that there was an absolute standard of rest, then he was just mistaken---there is no evidence of such a thing.
