3.1 Part I: Space is A Priori (Points 1 & 2)

Kant first establishes that space is not an empirical concept derived from outer experience, but the necessary condition for it.

Original Source Text (German B Edition)

§ 2, Nr. 1 (Presupposition)
Der Raum ist kein empirischer Begriff, der von äußeren Erfahrungen abgezogen worden. Denn damit gewisse Empfindungen auf etwas außer mir bezogen werden (d. i. auf etwas in einem andern Orte des Raumes, als darin ich mich befinde), imgleichen damit ich sie als außer und neben einander, mithin nicht bloß verschieden, sondern als in verschiedenen Orten vorstellen könne, dazu muß die Vorstellung des Raumes schon zum Grunde liegen. Demnach kann die Vorstellung des Raumes nicht aus den Verhältnissen der äußern Erscheinung durch Erfahrung erborgt sein, sondern diese äußere Erfahrung ist selbst nur durch gedachte Vorstellung allererst möglich.

(Kant, KrV B 38)

§ 2, Nr. 2 (Necessity)
Der Raum ist eine nothwendige Vorstellung a priori, die allen äußeren Anschauungen zum Grunde liegt. Man kann sich niemals eine Vorstellung davon machen, daß kein Raum sei, ob man sich gleich ganz wohl denken kann, daß keine Gegenstände darin angetroffen werden. Er wird also als die Bedingung der Möglichkeit der Erscheinungen und nicht als eine von ihnen abhängende Bestimmung angesehen und ist eine Vorstellung a priori, die nothwendiger Weise äußeren Erscheinungen zum Grunde liegt.

(Kant, KrV B 38)

English Translation (Kemp Smith)

To: Point 1 – The Outer Sense Argument
Space is C: not an empirical concept which has been derived from outer experiences. For in order that certain sensations be referred to something outside me (that is, to something in another region of space from that in which I find myself), and similarly in order that I may be able to represent them as outside and alongside one another, and accordingly as not only different but as in different places, the representation of space must be P: presupposed. The representation of space cannot, therefore, be empirically obtained from the relations of outer appearance. On the contrary, this outer experience is itself possible at all only through that representation.

(B38 / A23)

To: Point 2 – The Necessity Argument
Space is a C: necessary a priori representation, which underlies all outer intuitions. We can never represent to ourselves the P: absence of space, though we can quite well think it as empty of objects. It must therefore be regarded as the condition of the possibility of appearances, and not as a determination dependent upon them. It is an a priori representation, which necessarily underlies outer appearances.

(B38 / A24)

Argument Reconstruction: Space is A Priori

  • Point 1 (Outer Sense): To refer sensations to something “outside me,” I must already have the representation of space. Therefore, space is not derived from outer experience; outer experience is derived from space.
  • Point 2 (Necessity): We can think of space empty of objects, but never of objects without space. Space is a necessary representation a priori.

3.1.2 ASPIC+ Argument Reconstruction

Argument A (Not Empirical / Outer Sense)
  Premises:
    P1: Referring sensations "outside me" requires the representation of space (Strict).
    P2: "Outside me" means structurally distinct in location, not just distinct in sensation (Strict).
    P3: The condition of possibility (Space) cannot be derived from what it makes possible (Experience) (Strict).
  Conclusion:
    C1: Representation of space precedes outer experience (Space is not empirical).

  Attacks:
    - Empiricist Attack (Undercut): Space is an abstraction from the relations of objects (Leibniz/Hume).
      * Defense (Circular): To abstract "relations" of placement, one must already presuppose the space in which they are placed (P1).

Argument B (Necessity / A Priori)
  Premises:
    P4: We can represent space without objects (Empty Space) (Strict).
    P5: We cannot represent objects without space (Strict).
  Conclusion:
    C2: Space is a necessary representation (A Priori Condition).

  Attacks:
    - Nominalist Attack (Rebuttal): Space is a fiction/concept, not a real necessity.
      * Defense (Necessity): A fiction can be removed from thought; Space cannot be removed without collapsing the possibility of outer intuition (P5).