Do I worship modern medicine? Is science my religion? Not at all; there is no aspect of modern medicine or science that I would exempt from the most rigorous scrutiny, and I can readily identify a host of serious problems that still need to be fixed. That's easy to do, of course, because the worlds of medicine and science are already engaged in the most obsessive, intensive, and humble self-assessments yet known to human institutions, and they regularly make public the results of their self-examinations. Moreover, this open-ended rational criticism, imperfect as it is, is the secret of the astounding success of these human enterprises. There are measurable improvements every day. Had I had my blasted aorta a decade ago, there would have been no prayer of saving me. It's hardly routine today, but the odds of my survival were actually not so bad (these days, roughly 33 percent of aortic dissection patients die in the first twenty-four hours after onset without treatment, and the odds get worse by the hour thereafter).

One thing in particular struck me when I compared the medical world on which my life now depended with the religious institutions I have been studying so intensively in recent years. One of the gentler, more supportive themes to be found in every religion (so far as I know) is the idea that what really matters is what is in your heart: if you have good intentions, and are trying to do what (God says) is right, that is all anyone can ask. Not so in medicine! If you are wrong—especially if you should have known better—your good intentions count for almost nothing. And whereas taking a leap of faith and acting without further scrutiny of one's options is often celebrated by religions, it is considered a grave sin in medicine. A doctor whose devout faith in his personal revelations about how to treat aortic aneurysm led him to engage in untested trials with human patients would be severely reprimanded if not driven out of medicine altogether. There are exceptions, of course. A few swashbuckling, risk-taking pioneers are tolerated and (if they prove to be right) eventually honored, but they can exist only as rare exceptions to the ideal of the methodical investigator who scrupulously rules out alternative theories before putting his own into practice. Good intentions and inspiration are simply not enough.

In other words, whereas religions may serve a benign purpose by letting many people feel comfortable with the level of morality they themselves can attain, no religion holds its members to the high standards of moral responsibility that the secular world of science and medicine does! And I'm not just talking about the standards 'at the top'—among the surgeons and doctors who make life or death decisions every day. I'm talking about the standards of conscientiousness endorsed by the lab technicians and meal preparers, too. This tradition puts its faith in the unlimited application of reason and empirical inquiry, checking and re-checking, and getting in the habit of asking "What if I'm wrong?" Appeals to faith or membership are never tolerated. Imagine the reception a scientist would get if he tried to suggest that others couldn't replicate his results because they just didn't share the faith of the people in his lab! And, to return to my main point, it is the goodness of this tradition of reason and open inquiry that I thank for my being alive today.