often happens, that what according to _one_ form of our principle is _consequence_, is, according to another, _reason_. The rising of the quicksilver in a thermometer, for instance, is the _consequence_ of increased heat according to the law of causality, while according to the principle of the sufficient reason of knowing it is the _reason_, the ground of knowledge, of the increased heat and also of the judgment by which this is asserted. § 37. _Reason of Being in Space._ The position of each division of Space towards any other, say of any given line--and this is equally applicable to planes, bodies, and points--determines also absolutely its totally different position with reference to any other possible line; so that the latter position stands to the former in the relation of the consequent to its reason. As the position of this given line towards any other possible line likewise determines its position towards all the others, and as therefore the position of the first two lines is itself determined by all the others, it is immaterial which we consider as being first determined and determining the others, _i.e._ which particular one we regard as _ratio_ and which others as _rationata_. This is so, because in Space there is no succession; for it is precisely by uniting Space and Time to form the collective representation of the complex of experience, that the representation of coexistence arises. Thus an analogue to so-called reciprocity prevails everywhere in the Reason of Being in Space, as we shall see in § 48, where I enter more fully into the reciprocity of reasons. Now, as every line is determined by all the others just as much as it determines them, it is arbitrary to consider any line merely as determining and not as being determined, and the position of each towards any other admits the question as to its position with reference to some other line, which second position necessarily determines the first and makes it that which it is. It is therefore just as impossible to find an end _a parte ante_ in the series of links in the chain of Reasons of Being as in that of Reasons of Becoming, nor can we find any _a parte post_ either, because of the infinity of Space and of the lines possible within Space. All possible relative spaces are figures, because they are limited; and all these figures have their Reason of Being in one another, because they are conterminous. The _series rationum essendi_ in Space therefore, like the _series rationum fiendi_, proceeds _in infinitum_; and moreover not only in a single direction, like the latter, but in all directions. Nothing of all this can be proved; for the truth of these principles is transcendental, they being directly founded upon the intuition of Space given us _à priori_. § 38. _Reason of being in Time. Arithmetic._