all respects impossible, and that, consequently, the thing itself, of which this is the opposite, is absolutely necessary; but I cannot reason conversely and say, the opposite of that which is absolutely necessary is intrinsically impossible, that is, that the absolute necessity of things is an internal necessity. For this internal necessity is in certain cases a mere empty word with which the least conception cannot be connected, while the conception of the necessity of a thing in all relations possesses very peculiar determinations. Now as the loss of a conception of great utility in speculative science cannot be a matter of indifference to the philosopher, I trust that the proper determination and careful preservation of the expression on which the conception depends will likewise be not indifferent to him. In this enlarged signification, then, shall I employ the word absolute, in opposition to that which is valid only in some particular respect; for the latter is restricted by conditions, the former is valid without any restriction whatever. Now the transcendental conception of reason has for its object nothing else than absolute totality in the synthesis of conditions and does not rest satisfied till it has attained to the absolutely, that is, in all respects and relations, unconditioned. For pure reason leaves to the understanding everything that immediately relates to the object of intuition or rather to their synthesis in imagination. The former restricts itself to the absolute totality in the employment of the conceptions of the understanding and aims at carrying out the synthetical unity which is cogitated in the category, even to the unconditioned. This unity may hence be called the rational unity of phenomena, as the other, which the category expresses, may be termed the unity of the understanding. Reason, therefore, has an immediate relation to the use of the understanding, not indeed in so far as the latter contains the ground of possible experience (for the conception of the absolute totality of conditions is not a conception that can be employed in experience, because no experience is unconditioned), but solely for the purpose of directing it to a certain unity, of which the understanding has no conception, and the aim of which is to collect into an absolute whole all acts of the understanding. Hence the objective employment of the pure conceptions of reason is always transcendent, while that of the pure conceptions of the understanding must, according to their nature, be always immanent, inasmuch as they are limited to possible experience.