 Like all of Fichte’s systematic treatises of the Jena period, The System of Ethics begins with a detailed analysis of what is involved in the self-positing of the I. In this case, the focus is upon the necessity that the I posit for itself its own activity or “efficacy,” and upon a detailed analysis of the conditions for doing this. In this manner Fichte deduces what he calls “the principle of all practical philosophy,” viz., that something objective (a being) follows from something subjective (a concept), and hence that the I must ascribe to itself a power of free purposiveness or causality in the sensible world. The I must posit itself as an embodied will, and only as such does it “discover” itself at all. From this starting point Fichte then proceeds to a deduction of the principle of morality: namely, that I must think of my freedom as standing under a certain necessary law or categorical imperative, which Fichte calls “the law of self-sufficiency” or “autonomy,” and that I ought always to determine my freedom in accordance with this law. This, therefore, is the task of the philosophical science of “ethics,” as understood by Fichte: to provide an a priori deduction of our moral nature in general and of our specific duties as human beings.