I would by all means have men beware, lest Æsop's pretty fable of the fly that sate [sic] on the pole of a chariot at the Olympic races and said, 'What a dust do I raise,' be verified in them. For so it is that some small observation, and that disturbed sometimes by the instrument, sometimes by the eye, sometimes by the calculation, and which may be owing to some real change in the heaven, raises new heavens and new spheres and circles.
The first question concerning the Celestial Bodies is whether there be a system, that is whether the world or universe compose together one globe, with a center, or whether the particular globes of earth and stars be scattered dispersedly, each on its own roots, without any system or common center.
Nay, number itself in armies importeth not much, where the people is of weak courage; for, as Virgil saith, It never troubles the wolf how many the sheep be.
Men of noble birth are noted to be envious towards new men when they rise. For the distance is altered, and it is like a deceit of the eye, that when others come on they think themselves go back.
One always starts work with the subject, no matter how tenuous it is, and one constructs an artificial structure by which one can trap the reality of the subject-matter that one has started from.
Again men have been kept back as by a kind of enchantment from progress in science by reverence for antiquity, by the authority of men counted great in philosophy, and then by general consent.
The human understanding is of its own nature prone to suppose the existence of more order and regularity in the world than it finds. And though there be many things in nature which are singular and unmatched, yet it devises for them parallels and conjugates and relatives which do not exist. Hence the fiction that all celestial bodies move in perfect circles, spirals and dragons being (except in name) utterly rejected.