Notes on <Prolegomena to Any Future Metaphysics> - Introduction

2020-06-20 0 views

Background

Prolegomena is book wrote after the publication of Critique of Pure Reason, and is intended to be a preparatory exercise to CPR. That’s why people typically read Prolegomena before reading CPR.

Preface

After looking at the history of metaphysics, Kant raises the question that why metaphysics seems to be always saying the same things, and can not attain universal and lasting claims as other sciences did. This leads to the doubt that whether metaphysics is even possible as a science. Here science has a broader sense than what we know today, it means a systematic body of knowledge. We’ll find this is one of the final question Kant want to answer in his Critique of Pure Reason as well.

The major problem Kant want to address is actually from David Hume, who questions the validity of necessary connection of cause and effect. Hume proved that it is simply not to be seen how it could be that because something is, something else necessarily must also be, that is, how the concept of such a connection could be introduced a priori. Therefore Hume thinks the concept of cause and effect is passing off from the subjective necessity(i.e. habit) for an objective necessity. From which he concluded that reason has no power at all to think such connections, because its concepts would then be bare fictions, and there is no metaphysics at all and cannot be any.

Kant started with the concept of cause and effect and tries to find other similar concepts that are needed a priori for understanding and proceeded to a deduction of these concepts. With this deduction we can determine the entire extent of pure reason with regard to its boundaries and content, which is required to build metaphysics.

Interestingly, Kant is pretty accurate in predicting the possible reactions about his work, and he says the dryness and exactness of CPR is because he cares more about the well being of the science rather than the popularity of the work, so he sacrifices initial popularity, but expects a later and lasting approval.

Preamble on the Distinguishing Feature of All Metaphysical Cognition

  1. According to distinguishing feature of the source of metaphysical cognition, it is a cognition a priori, or from pure understanding and pure reason.
  2. Distinction between synthetic and analytic judgments Analytic judgments are explicative, which means they add nothing to the content of the cognition, everything in predicate is already contained in the subject and it will be a contradiction to deny the truth of analytic judgments. Analytic judgments are a priori by nature, even if their concepts are empirical.

Synthetic judgments are ampliative, which means they augment the given cognition. Synthetic judgments may be a posteriori, whose origin is empirical. There are also a priori synthetic judgments and that arise from pure understanding and reason. Synthetic judgments can be further classified:

  • Judgments of experience are always synthetic and without necessity.
  • Mathematical judgments are one and all synthetic. A synthetic proposition can be discerned in accordance with the principle of contradiction, but only insofar as another synthetic proposition is presupposed from which the first can be deduced, never however in itself. Mathematical judgments are also a priori because they carry the necessity which is not found in empirical judgments. Propositions like 7 + 5 = 12 or straight line between two points is the shortest are synthetic because the concept of predicate can’t be derived from subject analytically, and intuition must be made use here. The predicate attaches to such concepts indeed necessarily, though not immediately, but rather through an intuition that has to be added.

An essential feature of pure mathematical cognition is that it must throughout proceed not from concepts, but always and only through the construction of concepts. It must go beyond the concept to that which is contained in the intuition corresponding to it.

  • Properly metaphysical judgments are one and all synthetic. Proper metaphysical judgments are the aims of analytical metaphysical judgments, and are always synthetic. Proper metaphysics possesses something special and proper to it in the generation of its a priori cognitions. e.g. All that is substance in things persists, is a synthetic and properly metaphysical proposition.

The generation of cognition a priori in accordance with both intuition and concepts, ultimately of synthetic propositions a priori as well, and specifically in philosophical cognition, forms the essential content of metaphysics.

General Question of the Prolegomena: Is metaphysics possible at all?

Weary of dogmatism, which teaches us nothing, and also of skepticism, which promises us absolutely nothing at all, with respect to any knowledge that we believe we possess or that offers itself to us under the title of pure reason, there remains left for us but one critical question: Is metaphysics possible at all?

In CPR, Kant worked on the question synthetically, by inquiring within pure reason itself, and seeking to determine within this source both the elements and the laws of its pure use, according to principles. Prolegomena should be a preparatory exercise; they ought more to indicate what needs to be done in order to bring a science into existence if possible, than to present the science itself. The methodological procedure of prolegomena will be analytic. Analytic here means that we start from object in concreto, or its actuality and then proceed to the ground of its possibility, instead of the synthetic approach, which is starting from concept in abstracto. This is probably similar to progressive and regressive distinctions, where analytic is the same as regressive, ascending and synthetic the same as progressive, descending.

We cannot say metaphysics as a science is actual, but we can confidently say that some pure synthetic cognition a priori is actual and given, that pure mathematics and pure natural science are actual and given. We only need to ask how these sciences are possible and from their principles we can derive the possibility of all other synthetic cognition a priori.

General Question: How is cognition from pure reason possible?

It’s evident that analytic a priori judgments and synthetic a posteriori judgments are possible. It remains only that how are synthetic a priori judgments possible(They are possible because plenty of them are already given). The exact question we want to ask is:

How are synthetic propositions a priori possible?

We must find the foundation of the legitimacy of synthetic a priori judgments before we proceed to other inquires since it’s not based on principle of contradiction as analytic judgments, we must find some other foundations.

Reason why there is not yet an answer to this question is 1. it is never asked before 2. the difficulty of answering such a question.

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