Fundamental Principles of the Metaphysic of Morals - The Original Classic Edition

Kant is not considered as one of the more accessible philosophers, and most of his monumental works are too long and beyond reach of an average reader. This short book is still fairly advanced and conceptually sophisticated, but fortunately due to its length it does not go much too deep in philosophical concepts.

The book deals on several occasions with the central concept in Kants moral philosophy, and that is the concept of categorical imperative. This imperative can be summed up in Kants famous dictum: Act only according to that maxim whereby you can at the same time will that it should become a universal law.

Several other famous Kant concepts - like practical reason, pure reason, treating humans like ends and not as means in moral considerations, etc. - are dealt with throughout the book. You might need to read the book several times before you get a better understanding of what is being discussed, but again, since it is so short, this can be easily done.

The language of the translation sounds a bit archaic to the modern ear, but this does not obscure the meaning at all. Overall, reading this book would be a worthwhile endeavor and as good of a starting point to start reading Kant as they come.