Mindy runs up to Chase and apologizes for her earlier behavior; she's just worried about Brandon and thinks this could all be her fault. You see, she thinks her "rough" sex is what made Brandon so sick. The friction of her cotton shirt rubbing against him may well have caused those rashes, but that's about it. Keep thinking you're that awesome in bed though, Mindy.
Jodi Matthews says she had some yellow-colored mucus last week, and has brought in one of those paint swatches you get at The 'Pot (a.k.a. Home Depot) to show House the exact color: pale goldenrod. Jodi asks if she should be worried. "Oh yes! Very," House says. But more about the status of her employment than that of her mucus. You see, Jodi is about to get fired. "You're not a very nice doctor, are you?" Jodi understatement of the years. House explains that he can see that Jodi has been taking advantage of her job's health insurance before it is taken away; he noticed her new glasses and nice, white teeth. Me, I'd think she brushed and flossed regularly and took good care of the things that enabled her to see the world, but that's me. House is House, and he's right. "I just don't like being told what to do," says Jodi. Of all the things she could have said, that was probably the one thing that could tug on House's sole remaining heartstring. He almost smiles as he agrees to schedule Jodi for a full body scan. Awww. They should hang out.
Meanwhile, the Cottages are running lab tests. Hey, maybe the reason those tests are so unreliable is because doctors are doing them instead of the medical technologists who are actually trained for it. Chase laughs as he tells the group how Mindy thinks she "rode" Brandon to death. Cameron doesn't think it's very funny. She tells Chase he shouldn't have dismissed Mindy outright like that; any information is important right now. "Have you ever 'taken a life'?" asks Chase-o Suavé. Foreman interrupts with some news: the latest test results show that those antibiotics House prescribed have made Brandon's lungs fill with fluid and shut down his kidneys. The Magic School Bus Cam tries to enter what I'm guessing are pores of Brandon's CGI kidneys, but they keep hilariously shutting closed in its face until it gives up. "Our treatment isn't making him better," Foreman concludes. "It's killing him." Well, of course.
Now House and the Cottages have seven symptoms to work with. Foreman has a theory: Brandon has a viral heart infection, which is causing the low blood pressure, which in turn is causing the abdominal pain, since his intestines aren't getting enough blood. Foreman admits that it's a long shot, but says it does explain most of the symptoms. "Impressive," says House. Chase frowns, because he likes to be the person who gets all the right answers. House can't praise someone without immediately tearing him down, so he adds that Foreman's theory sucks because it doesn't explain the cough or the rash. He gets to his feet (both of them, and without using his cane, so he's precariously balanced on his good leg) and starts making circles all over the whiteboard with different-colored markers. Each color represents a possible theory and circles all of the symptoms it covers. House Venn Diagrams that only the orange and green circles cover all the symptoms. Therefore, Brandon has both of them. The Cottages laugh at the chances of Brandon contracting two things at the same time, Foreman saying the titular line that the Occam's Razor principle -- the simplest solution is always correct -- should apply here. And one illness is simpler than two. House offers up an example of how two can be simpler than one that involves human reproduction and that Foreman calls "specious." House responds by calling Foreman's tie ugly. They're both right, although only one of them acted like a petulant child.