Prof. Muni Mahendra Kumar
The most important contribution to the philosophy of space and time in the century following Newton and Leibnitz was that of Kant (1724-1804). Being a supporter of the doctrine of idealism, Kant did not accept space and time as objective realities. In his view, space and time exist in the consciousness, antecedently to all experience-it is an a priori form of our sensibility or intuition. Kant presented space and time as analogous forms of visualisation and treated them in a common chapter in his major epistemological work.[1] He has given four metaphysical arguments to prove his theory of space.
- Space is not a conception which has been derived from outward experiences. For, in order that certain sensations may relate to something without me (that is, to something which occupies a different part of space from that in which I am); in like manner, in order that I may represent them not merely as without of and near to each other, but also in separate places, the representation of space must already exist as a foundation. Consequently, the representation of space cannot be borrowed from the relations of external phenomena through experience; but on the contrary, this external experience is itself only possible through the said antecedent representation.
- Space then is a necessary representation a priori, which serves for the foundation of all external institutions. We never can imagine or make a representation to ourselves of the non-existence of space, though we may easily enough think that no objects are found in it. It must, therefore be considered as the condition of the possibility of phenomena, and by no means as a determination dependent on them, and is a representation a priori which necessarily supplies the basis for external phenomena.
- Space is no discursive, or as we say, general conception of the relations of things but a pure intuition. For in the first place, we can only represent to ourselves one space, and when we talk of diverse spaces, we mean only parts of one and the same space. Moreover these parts cannot antecede this one all-embracing space, as the component parts from which the aggregate can be made up, but can be cogitated only as existing in it. Space is essentially one, and multiplicity in it, consequently the general notion of spaces, of this or that space, depends solely upon limitations. Hence it follows that an a priori intuition (which is not empirical) lies at the root of all our conceptions of space. Thus, moreover, the principles of geometry- for example, that "in a triangle, two sides together are greater than the third," are never deduced from general concep-tions of line and triangle, but from intuition, and this is a priori with apodictic certainty.
- Space is represented as an infinite given quantity. Now every conception must indeed be considered as a representation which is contained in an infinite multitude of different possible representations, which, therefore, comprises these under itself but no conception, as such, can be so conceived, as if it contained within itself an infinite multitude of representations. Nevertheless, space is so conceived of, for all parts of space are equally capable of being produced to infinity. Consequently, the original representation of space is an intution a priori, and not a conception."[2]
Thus, Kant asserted that space and time have no existence except as a characteristic of human consciousness. Kant inferred from his theory of space that "all geometrical propositions can be deduced a priori from intuition, with apodeictical certainty". On the strength of this assertion, he believed that Euclidean geometry[3] was infallibly true, and indeed was a necessity of thought.
We see, thus, that different philosophers have placed forth different views on space and time. It is to be noted that the scientific outlook has been greatly influenced by these philosophical ideas; this should not surprise us, for the concept of space and time are as much related to physics as to philosophy.
