No great discovery was ever made without a bold guess.

Thus you may multiply each stone 4 times & no more for they will then become oyles shining in ye dark and fit for magicall uses. You may ferment them with gold and silver, by keeping the stone and metal in fusion together for a day, & then project upon metalls. This is the multiplication of ye stone in vertue. To multiply it in weight ad to it of ye first Gold whether philosophic or vulgar.

You ask me how, with so much study, I manage to retene my health. Morpheus is my last companion; without 8 or 9 hours of him yr correspondent is not worth one scavenger's peruke. My practices did at ye first hurt my stomach, but now I eat heartily enou' as y' will see when I come down beside you.

To every action there is always opposed an equal reaction.

Trials are medicines which our gracious and wise Physician prescribes because we need them; and he proportions the frequency and weight of them to what the case requires. Let us trust his skill and thank him for his prescription.

If I have done the public any service, it is due to my patient thought.

I have presented principles of philosophy that are not, however, philosophical but strictly mathematical-that is, those on which the study of philosophy can be based. These principles are the laws and conditions of motions and of forces, which especially relate to philosophy.