We are certainly not to relinquish the evidence of experiments for the sake of dreams and vain fictions of our own devising; nor are we to recede from the analogy of Nature, which is wont to be simple and always consonant to itself.

There is no result in nature without a cause; understand the cause and you will have no need of the experiment.

Necessity is the mistress and guide of nature.

Do not imitate one another's style. If you do, so far as your art is concerned you will be called a grandson, rather than the son of Nature. It is always best to have recourse to nature, which is replete with such abundance of objects, than to the productions of other masters, who learnt everything from her.

Human subtlety will never devise an invention more beautiful, more simple or more direct than does nature because in her inventions nothing is lacking, and nothing is superfluous.

Although nature commences with reason and ends in experience it is necessary for us to do the opposite, that is to commence with experience and from this to proceed to investigate the reason.