Peter Kreeft(Dr. Peter Kreeft teaches philosophy at Boston College. He is a renowned Catholic apologists. The following is an excerpt from an article in his series Pillars of Unbelief. The second article considers Immanuel Kant, his philosophy and his subjectification of truth. It can be read in its entirety here.) Kant - Subjectivizer of Truth
Few philosophers in history have been so unreadable and dry as Immanuel Kant. Yet few have had a more devastating impact on human thought.
Kant's devoted servant, Lumppe, is said to have faithfully read each thing his master published, but when Kant published his most important work, "The Critique of Pure Reason," Lumppe began but did not finish it because, he said, if he were to finish it, it would have to be in a mental hospital. Many students since then have echoed his sentiments.
Yet this abstract professor, writing in abstract style about abstract questions, is, I believe, the primary source of the idea that today imperils faith (and thus souls) more than any other; the idea that truth is subjective.
The simple citizens of his native Konigsburg, Germany, where he lived and wrote in the latter half of the 18th century, understood this better than professional scholars, for they nicknamed Kant "The Destroyer" and named their dogs after him.
He was a good-tempered, sweet and pious man, so punctual that his neighbors set their clocks by his daily walk. The basic intention of his philosophy was noble: to restore human dignity amidst a skeptical world worshiping science.
This intent becomes clear through a single anecdote. Kant was attending a lecture by a materialistic astronomer on the topic of man's place in the universe. The astronomer concluded his lecture with: "So you see that astronomically speaking, man is utterly insignificant." Kant replied: "Professor, you forgot the most important thing, man is the astronomer."
Kant, more than any other thinker, gave impetus to the typically modern turn from the objective to the subjective. This may sound fine until we realize that it meant for him the redefinition of truth itself as subjective. And the consequences of this idea have been catastrophic.
If we ever engage in conversation about our faith with unbelievers, we know from experience that the most common obstacle to faith today is not any honest intellectual difficulty, like the problem of evil or the dogma of the trinity, but the assumption that religion cannot possibly concern facts and objective truth at all; that any attempt to convince another person that your faith is true—objectively true, true for everyone—is unthinkable arrogance.
The business of religion, according to this mindset, is practice and not theory; values, not facts; something subjective and private, not objective and public. Dogma is an "extra," and a bad extra at that, for dogma fosters dogmatism. Religion, in short, equals ethics. And since Christian ethics is very similar to the ethics of most other major religions, it doesn't matter whether you are a Christian or not; all that matters is whether you are a "good person." (The people who believe this also usually believe that just about everyone except Adolf Hitler and Charles Manson is a "good person.")
Kant is largely responsible for this way of thinking. He helped bury the medieval synthesis of faith and reason. He described his philosophy as "clearing away the pretensions of reason to make room for faith"—as if faith and reason were enemies and not allies. In Kant, Luther's divorce between faith and reason becomes finalized...
In our last post on Genesis we talked about how the sin of Adam had thrown everything out of balance. The world was no longer a temple as it was before. Man had literally fallen out of God's grace. He was now estranged from God though not entirely. God promises to send a redeemer to save man and defeat evil once and for all. (More on this in a later post.) Last but not least, man's relationship with man and with woman was forever transformed. Brother would fight against and kill brother. Marriage would no longer be predicated on love. Instead, the battle of the sexes had begun. This was not part of God's original plan but a consequence of original sin. 
