Having given up autonomy, reason has become an instrument. — Max Horkheimer

"In most cases, to be reasonable means not to be obstinate, which in turn points to conformity with reality as it is. The principle of adjustment is taken for granted. When the idea of reason was conceived, it was intended to achieve more than the mere regulation of the relation between means and ends: it was regarded as the instrument for understanding the ends, for determining them."

"Subjective reason … is inclined to abandon the fight with religion by setting up two different brackets, one for science and philosophy, and one for institutionalized mythology, thus recognizing both of them. For the philosophy of objective reason there is no such way out. Since it hold to the concept of objective truth, it must take a positive or a negative stand with regard to the content of established religion."

"Notwithstanding their attacks on the basic conception of rationalism, on synthetic a priori judgments, that is, material propositions that cannot be contradicted by any experience, the empiricist posits the forms of being as constant."

"The complexity of the connection between the world of perception and the world of physics does not preclude that such a connection can be shown to exist at any time."

"At present, when the prevailing forms of society have become hindrances to the free expression of human powers, it is precisely the abstract branches of science, mathematics and theoretical physics, which … offer a less distorted form of knowledge than other branches of science which are interwoven with the pattern of daily life, and the practicality of which seemingly testifies to their realistic character."

"Leibniz’s theory on the subject as substantia ideans in the sense of a causative agent of decision and acts stands much closer to a materialist interpretation of history than does a philosophy which reduces the thinking subject to the role of subsuming protocol sentences under general propositions and deducing other sentences from them."