arts and sciences; and the incomparable perspicacity of your
intellect is evinced by this, that you penetrated the secrets of the
sciences and acquired an accurate knowledge of them in a very short
period. But of the vigour of your intellect I have a still stronger
proof, and one peculiar to myself, in that I have never yet met any
one who understood so generally and so well as yourself all that is
contained in my writings. For there are several, even among men of
the highest intellect and learning, who find them very obscure. And
I remark, in almost all those who are versant in Metaphysics, that
they are wholly disinclined from Geometry; and, on the other hand,
that the cultivators of Geometry have no ability for the
investigations of the First Philosophy: insomuch that I can say with
truth I know but one mind, and that is your own, to which both
studies are alike congenial, and which I therefore, with propriety,
designate incomparable. But what most of all enhances my admiration
is, that so accurate and varied an acquaintance with the whole
circle of the sciences is not found in some aged doctor who has
employed many years in contemplation, but in a Princess still young,
and whose countenance and years would more fitly represent one of
the Graces than a Muse or the sage Minerva. In conclusion, I not
only remark in your Highness all that is requisite on the part of
the mind to perfect and sublime wisdom, but also all that can be
required on the part of the will or the manners, in which benignity
and gentleness are so conjoined with majesty that, though fortune
has attacked you with continued injustice, it has failed either to
irritate or crush you. And this constrains me to such veneration
that I not only think this work due to you, since it treats of
philosophy which is the study of wisdom, but likewise feel not more
zeal for my reputation as a philosopher than pleasure in subscribing
myself,--