To believe that any action based on an ignorance of fact can possibly succeed, is to abandon the use of reason.

Reason is lost reasoning.

Reason as an organ for perceiving the true nature of reality and determining the guiding principles of our lives has come to be regarded as obsolete.

Reason spoiled, marred, or robbed of its perfection, ceaseth to be rational, and should not be called reason; inasmuch as it is premised to be depraved, or degenerated from a rational nature; and in consequence of the deprivation of its nature, should also be deprived of its name, and called subterfuge, or some such like name, which might better define its real character. Those who invalidate reason, ought seriously to consider, "whether they argue against reason, with or without reason; if with reason, then they establish the principle, that they are laboring to dethrone;" but if they argue without reason, (which, in order to be consistent with themselves, they must do,) they are out of the reach of rational conviction, nor do they deserve a rational argument.

Those who invalidate reason ought seriously to consider whether they argue against reason with or without reason; if with reason, then they establish the principle that they are laboring to dethrone: but if they argue without reason (which, in order to be consistent with themselves they must do), they are out of reach of rational conviction, nor do they deserve a rational argument.

We have rejected reason because we have found another reason that could be called trans-rational, which has its own law, construction, and sense.. .This reason has found a way-Cubism-of expressing the object.

Reason is the inextinguishable impulse to philosophize with whose destruction reason itself is destroyed.

Those who invalidate reason, ought seriously to consider, 'whether they argue against reason, with or without reason; if with reason, then they establish the principle, that they are laboring to dethrone;' but if they argue without reason, (which, in order to be consistent with themselves, they must do,) they are out of the reach of rational conviction, nor do they deserve a rational argument.

Accommodationists further accuse scientists of having “faith in reason.” Yet reason is not an a priori assumption, but a tool that’s been shown to work. We don’t have faith in reason; we use reason, and we use it because it produces results and progressive understanding...
Reason is simply the way we justify our beliefs, and if you’re not using it, whether you’re justifying religious or scientific beliefs, you deserve no one’s attention.

Reason has never really directed social reality, but now reason has been so thoroughly purged of any specific trend or preference that it has finally renounced even the task of passing judgment on man’s actions and way of life. Reason has turned them over for ultimate sanction to the conflicting interests to which our world actually seems abandoned.

Reason alone does not suffice.

Rationality is wasted if you don’t know when to use it.

I applied my reason at every moment. Reason is excellent for getting food, clothing and shelter. Reason is the very best tool kit. Nothing beats reason for keeping tigers away. But be excessively reasonable and you risk throwing out the universe with the bathwater.

The rehabilitation of reason is urgent because it is only through the proper use of reason that we can find our way out of the quagmires in which many big issues of our time have become stuck. Without a clear sense of what it means for one point of view to be more reasonable than another, it seems that the position one adopts is ultimately based on nothing more than personal opinion or preference.