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1. LIFE is short, Art long, Experience not easily obtained, Judgement difficult, and therefore it is necessary, that a Student not only exercise himself in considering several Figures, but also that he diligently read the writings of others who have treated rationally of this Science, and make it his business to find out the true natural causes of things by experiments, to know the certain places and processions of tee Planets and Fixed Stars, Constellations, etc., but above all to be a passionate lover of truth.

2. The Principles of Art are three, Reason, Sense, and Experience, but the Principles of Operations four, viz: The Planets, The Parts of Heaven, The Fixed Stars, and the Site or Position of all those in respect of one another.

3. There are some things perfectly known, as the Circle of Ascension, some in a competent measure, as the Revolution of the Sun; some may be known although they yet are not, as the Revolution of the Superiors; some things fall under knowledge, yet cannot be exactly known, as the precise Ingress of the Sun into the Equinoctial Point; some are neither known, nor can be known, as the complete commixtures and distinct virtues of all the Stars.

4. It is much worse for an Artist to conceive he knows those things, which he is ignorant of, than to be ignorant of those things which he ought to know.

5. Mean learning with an excellent judgement, avails more than a mean judgement with the greatest learning, :yet is judgement very much assisted and perfected by learning: but everything prospers better, and is far more easily perfected that has nature for its guide and favourable stars, than that which is attempted by human industry though never so diligent.

6. He that has too great a conceit of himself will be apt to fall into many errors in his judgement; yet on the other side, he that is too diffident, is not fit for this Science.

7. He that would truly promote Art must insist as much on the confutation of false opinions delivered by others, as in the declaration of truth.

8. An Astrologer is so far only true and honest, as he depends in his conjectures on principles of natural philosophy, and since those Arts which are inherent in their proper subjects, cannot promise any certainty concerning matters to come, the Astrologer ought never to pronounce anything absolutely or peremptorily of future contingencies,

9. Truths of themselves are to be desired, for Science itself is a certain good, now the expectation of future good very much delights us, and on the contrary, when future evils are foreseen, we may either avoid them, mitigate them, or at least bear them more contentedly.

10. Heaven is the instrument of the most High God, whereby he acts upon, and governs inferior things.

11. He that asserts thin~ that can never be proved by experience is deceived and ambitious, but thus it always happens, those that are most ignorant of Art delight to boast of doing things difficult or wonderful.

12. It is all one as to promoting of Art, etc., and the knowledge thereof, either from Nativities known, to predict what shall happen, or after accidents have happened, to discover the Nativities before unknown which are thereby rectified but as to vulgar opinion, the first way far exceeds the last.

13. He that goes about to destroy Art, is far worse than he that is unskilled in it, for his mind is full of malice and idleness as well as ignorance.

14. Men may be said almost to be compelled by the Stars, even in voluntary actions, by means of their corrupt affections and ignorance.

15. Always deliver judgements from the Stars in general terms, or if thou dost otherwise let it be when thou hast very evident testimonies and in great and weighty matters.

16. We ought not to use arguments or tedious discourses in giving judgement, much less flatteries, but only to pronounce what is known by experience and firm reason.

17. A main reason why events are so rarely foretold by Astrologers, is because the Art is yet but imperfectly discovered, for hitherto those that have been most excellent in it, being commonly old persons, have despaired to live to see the fortunes of children newly-born, and the Nativities of persons grown up, being uncertain, they scarce thought them worth so much labour.

18. When true genitures exactly taken in accidents prove false or absurd, and not agreeable to the things signified, they are to be accounted monstrous, and are to be avoided as anatomists do monstrous bodies in their dissections; for they overthrow Art,

19. Generals are to be gathered from Singulars, and Singulars from Generals, and an Artist ought always to learn to distinguish between that which is by itself, and that which is only by accident.

20. The strength and efficacy of Fixed Stars is to be considered from their magnitude, their splendours, their natures or properties, their nearness to the Ecliptic, their place in the World, their multitude, their first oriental appearance, the purity of their place, the similitude or agreement of the body or rays of a Planet with them and their circle of position.