far wanting in the duty I owe to myself, as to give occasion to those who
shall survive me to make it matter of reproach against me some day, that I
might have left them many things in a much more perfect state than I have
done, had I not too much neglected to make them aware of the ways in which
they could have promoted the accomplishment of my designs.

And I thought that it was easy for me to select some matters which should
neither be obnoxious to much controversy, nor should compel me to expound
more of my principles than I desired, and which should yet be sufficient
clearly to exhibit what I can or cannot accomplish in the sciences.
Whether or not I have succeeded in this it is not for me to say; and I do
not wish to forestall the judgments of others by speaking myself of my
writings; but it will gratify me if they be examined, and, to afford the
greater inducement to this I request all who may have any objections to
make to them, to take the trouble of forwarding these to my publisher, who
will give me notice of them, that I may endeavor to subjoin at the same
time my reply; and in this way readers seeing both at once will more easily
determine where the truth lies; for I do not engage in any case to make
prolix replies, but only with perfect frankness to avow my errors if I am
convinced of them, or if I cannot perceive them, simply to state what I
think is required for defense of the matters I have written, adding
thereto no explication of any new matte that it may not be necessary to
pass without end from one thing to another.

If some of the matters of which I have spoken in the beginning of the
"Dioptrics" and "Meteorics" should offend at first sight, because I call
them hypotheses and seem indifferent about giving proof of them, I request
a patient and attentive reading of the whole, from which I hope those
hesitating will derive satisfaction; for it appears to me that the
reasonings are so mutually connected in these treatises, that, as the last