_=Philosophiae moralis fons et fundamentum= utrum in idea moralitatis, quae immediate conscientia contineatur, et ceteris notionibus fundamentalibus, quae ex illa prodeant, explicandis =quaerenda sunt=, an in alio cognoscendi principio?_ (The original idea of morality, or the leading conception of the supreme moral law, occurs by a necessity which seems peculiar to the subject, but which is by no means a logical one, both in that science, whose object it is to set forth the knowledge of what is moral, and also in real life, where it shows itself partly in the judgment passed by conscience on our own actions, partly in our moral estimation of the actions of others; moreover, most of the chief conceptions in Ethics, springing as they do out of that idea, and inseparable from it (as, for instance, the conception of duty, and the ascription of praise or blame) assert themselves with the same necessity, and under the same conditions. In view of these facts and because it appears highly desirable, considering the trend of philosophic investigation in our time, to submit this matter to further scrutiny; the Society desires that the following question be carefully considered and discussed:-- =Is the fountain and basis of Morals to be sought for= in an idea of morality which lies directly in the consciousness (or conscience), and in the analysis of the other leading ethical conceptions which arise from it? or is it to be found an some other source of knowledge?) PART I. INTRODUCTION. CHAPTER I. THE PROBLEM. "Why do philosophers differ so widely as to the first principles of Morals, but agree respecting the conclusions and duties which they deduce from those principles?" This is the question which was set as subject for a prize essay by the Royal Society of Holland at Harlem, 1810, and solved by J.C.F. Meister; and in comparison with the task before us, the inquiry presented no extraordinary difficulty. For:--