LIFE is the faculty a being has of acting according to laws of the faculty of desire.
 Immanuel Kant, Critique of Practical Reason (1788). copy citation

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Author Immanuel Kant
Source Critique of Practical Reason
Topic desire law
Date 1788
Language English
Reference
Note Translated by Thomas Kingsmill Abbott
Weblink http://www.gutenberg.org/cache/epub/5683/pg5683-images.html

Context

“, and thus the supreme principle of practical philosophy would be necessarily made empirical, which, however, remains to be proved and in this critique is altogether refuted. It will, therefore, give this definition here in such a manner as it ought to be given, in order to leave this contested point open at the beginning, as it should be. LIFE is the faculty a being has of acting according to laws of the faculty of desire. The faculty of DESIRE is the being's faculty of becoming by means of its ideas the cause of the actual existence of the objects of these ideas. PLEASURE is the idea of the agreement of the object, or the action with the subjective conditions of life, i.e., with the faculty of causality of an idea in respect of the actuality of its object” source