be reli'd on. For though unwillingly, Yet I must for the truths sake,
and the Readers, warne him not to be forward to believe Chymical
Experiments when they are set down only by way of Prescriptions, and
not of Relations; that is, unless he that delivers them mentions his
doing it upon his own particular knowledge, or upon the Relation of
some credible person, avowing it upon his own experience. For I am
troubled, I must complain, that even Eminent Writers, both Physitians
and Philosophers, whom I can easily name, if it be requir'd, have of
late suffer'd themselves to be so far impos'd upon, as to Publish and
Build upon Chymical Experiments, which questionless they never try'd;
for if they had, they would, as well as I, have found them not to be
true. And indeed it were to be wish'd, that now that those begin to
quote Chymical Experiments that are not themselves Acquainted with
Chymical Operations, men would Leave off that Indefinite Way of
Vouching the Chymists say this, or the Chymists affirme that, and
would rather for each Experiment they alledge name the Author or
Authors, upon whose credit they relate it; For, by this means they
would secure themselves from the suspition of falshood (to which the
other Practice Exposes them) and they would Leave the Reader to Judge
of what is fit for him to Believe of what is Deliver'd, whilst they
employ not their own great names to Countenance doubtfull Relations;
and they will also do Justice to the Inventors or Publishers of true
Experiments, as well as upon the Obtruders of false ones. Whereas by
that general Way of quoting the Chymists, the candid Writer is
Defrauded of the particular Praise, and the Impostor escapes the
Personal Disgrace that is due to him._
_The remaining Part of this Praeface must be imploy'd in saying
something for_ Carneades, _and something for my Self._
_And first_, Carneades _hopes that he will be thought to have disputed
civilly and Modestly enough for one that was to play the Antagonist
and the Sceptick. And if he any where seem to sleight his Adversaries
Tenents and Arguments, he is willing to have it look'd upon as what he
was induc'd to, not so much by his Opinion of them, as the Examples
of_ Themistius _and_ Philoponus, _and the custom of such kind of
Disputes._
_Next, In case that some of his Arguments shall not be thought of the
most Cogent sort that may be, he hopes it will be consider'd that it
6