Where do you think that knowledge comes from? The first two years of medical school are all but forgotten, the third is key, and the fourth is mainly for interviews and vacation.
Most of the real training is in residency. An intern is far more worthless than a good PA, and so are many R2's or even R3's.
I'm not incredibly familiar with the PA curriculum, but they get most of the same courses we do, they basically just miss out on 4th year (which is mostly a waste anyway). So unlike NPs, PAs actually do get a foundation in basic science.
So personally, (and this is coming from an MD), if I had my choice I would definitely rather be treated by a PA than an intern.
Are you a resident? What year?
PAs (as drizzt stated) only go to school for 2 years. Their basic science curriculum is 1 year. Everything that we learn (at an absolute ultra-fast pace) they do in half the time, which really means they cut a significant portion out. If you don't have a foundation in the basic sciences can you really build a deep understanding of pathophysiology in the future?
You might say that we forget the first two years, but I would argue that this is not true. You might not remember every equation or every little detail, but I'll bet you still have all of the big picture concepts and could easily refresh and topic from MS1/2 in your head with the click of wikipedia.
Here is the curriculum of a local PA program:
First Year - Fall Quarter
Advanced Anatomy 4
Patient Communication 2
Ethical Issues in Physician Assistant Practice 2
Clinical Assessment 5
Physician Assistant Practice 2
Total 15
First Year - Winter Quarter
Epidemiology for Practice & Prevention 3
Principles of Medical Science I 2
Pharmacology and Therapeutics I 3
Clinical Medicine I 5
Clinical Skills I 2
Total 15
First Year - Spring Quarter
Principles of Medical Science II 2
Pharmacology and Therapeutics II 2
Biopsychosocial Issues in Patient Care 5
Clinical Medicine II 5
Clinical Skills II 2
Total 16
First Year - Summer Quarter
Health Policy for Physician Assistant Practice 2
Principles of Medical Science III 2
Pharmacology and Therapeutics III 2
Special Topics in Clinical Medicine 5
Clinical Skills III 4
Total 15
Second Year - Fall Quarter
Rotation I 5
Rotation II 5
Total 10
Second Year - Winter Quarter
Rotation III 5
Rotation IV 5
Graduate Project I 3
Total 13
Second Year - Spring Quarter
Rotation IV 5
Rotation VI 5
Total 10
Second Year - Summer Quarter
PA 635 Primary Care Practicum I 10
PA 638 Graduate Project II 3
Total 13
Third Year - Fall Quarter
Course Course Title Credits
PA 637 Primary Care Practicum II 10
Total 10
I don't see biochemistry, genetics, physiology, microbiology, immunology, embryology, nutrition, neuroscience. You really believe that the 2 credit courses of "Medical science" and pharm cover everything necessary to build a solid knowledge base upon?
PAs being looked at as "permanent residents" seems pretty accurate. But there's a reason they're permanently there - because they have no knowledge base to build upon (they just do pattern recognition) and because they usually perform the scut work that residents usually have to do but is not educational. Not to mention that PAs usually work 3-4 days a week. You can't compare a PA in practice for 10 years with a newly minted intern. But I would take a senior resident or fellow over a PA anyday.
Not to mention that all of fourth year really isn't a vacation. I worked pretty damn hard on all of my sub-i, research, and away rotations. Even my radiology rotation, which admittedly was easy, taught me a lot about radiology (much more than if I never had it at all like a PA).