If man has learned to see and know what really is, he will act in accordance with truth, Epistemology is in itself ethics, and ethics is epistemology. - Herbert Marcuse

German idealism rescued philosophy from the attack of British empiricism, and the struggle between the two became not merely a clash of different philosophical school, but a struggle for philosophy as such. P. 16

Loren von Stein thus turned the dialectic into an ensemble of objective laws calling for social reform as the adequate solution of all contradictions and neutralized the critical elements of the dialectic. P. 388

Can the human appropriation of nature ever achieve the elimination of violence, cruelty, and brutality in the daily sacrifice of animal life for the physical reproduction of the human race? To treat nature "for its own sake" sounds good, but it is certainly not for the sake of the animal to be eaten, nor probably for the sake of the plant. The end of this war, the perfect peace in the animal world — this idea belongs to the Orphic myth, not to any conceivable historical reality. In the face of the suffering inflicted by man on man, it seems terribly "premature" to campaign for universal vegetarianism or synthetic foodstuffs; as the world is, priority must be on human solidarity among human beings. And yet, no free society is imaginable which does not, under its "regulative idea of reason," make the concerted effort to reduce consistently the suffering which man imposes on the animal world.