Why I Love Descartes

then you’ll love Kant. My interpretation of the following is that he sees all metaphysics before his own as needing to be thrown out (or at least re-examined) after laying better epistemological foundations.

”
This much is certain, that whoever has once tasted Critique
will be ever after disgusted with all dogmatical twaddle which be
formerly put up with, because his reason must have something, and
could find nothing better for its support.

Critique stands in the same relation to the common
metaphysics of the schools, as chemistry does to alchemy, or as
astronomy to the astrology of the fortune-teller. I pledge myself
that nobody who has read through and through, and grasped the
principles of, the Critique even in these Prolegomena only, will
ever return to that old and sophistical pseudo-science; but will
rather with a certain delight look forward to metaphysics which
is now indeed in his power, requiring no more preparatory
discoveries, and now at last affording permanent satisfaction to
reason. For here is an advantage upon which, of all possible
sciences, metaphysics alone can with certainty reckon: that it
can be brought to such completion and fixity as to be incapable
of further change, or of any augmentation by new discoveries;
because here reason has the sources of its knowledge in itself,
not in objects and their observation [Anschauung], by which
latter its stock of knowledge cannot be further increased. When
therefore it has exhibited the fundamental laws of its faculty
completely and so definitely as to avoid all misunderstanding,
there remains nothing for pure reason to know a priori, nay,
there is even no ground to raise further questions. The sure
prospect of knowledge so definite and so compact has a peculiar
charm, even though we should set aside all its advantages, of
which I shall hereafter speak.

All false art, all vain wisdom, lasts its time, but finally
destroys itself, and its highest culture is also the epoch of its
decay. That this time is come for metaphysics appears from the
state into which it has fallen among all learned nations, despite
of all the zeal with which other sciences of every kind are
prosecuted. The old arrangement of our university studies still
preserves its shadow; now and then an Academy of Science tempts
men by offering prizes to write essays on it, but it is no longer
numbered among thorough sciences; and let any one judge for
himself how a man of genius, if he were called a great
metaphysician, would receive the compliment, which may be well-
meant, but is scarce envied by anybody.

….
Ever since I have come to know critique, whenever I finish
reading a book of metaphysical contents, which, by the
preciseness of its notions, by variety, order, and an easy style,
was not only entertaining but also helpful, I cannot help asking,
11 Has this author indeed advanced metaphysics a single step?”
The learned men, whose works have been useful to me in other
respects and always contributed to the culture of my mental
powers, will, I hope, forgive me for saying, that I have never
been able to find either their essays or my own less important
ones (though self-love may recommend them to me) to have advanced the science of metaphysics in the least, and why?

Here is the very obvious reason: metaphysics did not then
exist as a science, nor can it be gathered piecemeal, but its
germ must be fully preformed in the Critique. But in order to
prevent all misconception, we must remember what has been already
said, that by the analytical treatment of our concepts the
understanding gains indeed a great deal, but the science (of
metaphysics) is thereby not in the least advanced, because these
dissections of concepts are nothing but the materials from which
the intention is to carpenter our science. Let the concepts of
substance and of accident be ever so well dissected and
determined, all this is very well as a preparation for some
future use. But if we cannot prove, that in all which exists the
substance endures, and only the accidents vary, our science is
not the least advanced by all our analyzes.

Metaphysics has hitherto never been able to prove a priori
either this proposition, or that of sufficient reason, still less
any more complex theorem, such as belongs to psychology or
cosmology, or indeed any synthetical proposition. By all its
analyzing therefore nothing is affected, nothing obtained or
forwarded and the science, after all this bustle and noise, still
remains as it was in the days of Aristotle, though far better
preparations were made for it than of old, if the clue to
synthetical cognitions had only been discovered.

If any one thinks himself offended, he is at liberty to
refute my charge by producing a single synthetical proposition
belonging to metaphysics, which he would prove dogmatically a
priori, for until he has actually performed this feat, I shall
not grant that he has truly advanced the science; even should
this proposition be sufficiently confirmed by common experience.
No demand can be more moderate or more equitable, and in the
(inevitably certain) event of its non-performance, no assertion
more just, than that hitherto metaphysics has never existed as a
science.
”

”
My purpose is, to convince all those who care to trouble themselves with metaphysics, that it is indispensably necessary for the present to suspend their work, to look upon all that is gone before as non-existent, and, above all things, first to propose the question “Whether such a thing as metaphysics be even possible at all?”

If it be a science, how comes it that it cannot like other sciences win for itself a universal and lasting recognition? If it be not one, how is it that under the semblance of a science it is ceaselessly boasting and holding out to the human understanding hopes that are never extinguished and never fulfilled? Something must be definitely decided respecting the nature of this assumed science, whether it be to demonstrate our knowledge or our ignorance; for it is impossible that it should remain longer on the same footing as heretofore. It seems well-nigh ridiculous, while every other science ceaselessly progresses, that this which is supposed to be wisdom itself, whose oracle every one interrogates, is continually turning round on the same spot, without moving a step in advance. Its votaries have also much decreased, and we do not see those who feel themselves strong enough to shine in other sciences, willing to risk their fame in this, where every one, ignorant though he be in all else, ventures upon a decided opinion, because forsooth in this sphere there is no certain weight and measure at hand by which to distinguish profundity from worthless jargon.
“