HOUSTON, TEXAS — Former Housing and Urban Development Secretary Julian Castro went after Joe Biden hard during the third Democrat debate, asking if the former vice president had just forgotten what he said minutes before.

“Are you forgetting what you said two minutes ago? Are you forgetting already what you said just two minutes ago? I mean, I can’t believe that you said two minutes ago that they had to buy in and now you’re saying they don’t have to buy in. You’re forgetting that,” he said to Biden onstage during one of the more contentious moments.

Breitbart News asked Castro if he was going after Biden’s age — which has become a subject of discussion after several gaffes and memory lapses on the campaign trail.

Castro responded, “No, not at all. I was going after the difference that we have in health policy of what he had just said on the stage.”

He said Biden’s plan allows the uninsured to “buy in” or “opt in” to a public option, whereas his plan would enroll people automatically.

“The difference that he and I have is that his plan would leave 10 million people uncovered and my approach would cover everybody. It’s important what he said, because what he said is that you wouldn’t have to buy in — if you lose your job you would be automatically be able to buy in to his plan. That means a lot of people can’t buy in, they can’t afford it,” he said.

“And under my approach, you would automatically be enrolled — that’s a big distinction. So I pointed out, ‘Hey if you’re making people buy in, that’s going to leave people uncovered’ He denied saying buy-in, but if you look at the transcript, he actually said it,” he added.

Here is the exchange between Biden and Castro, according to the transcript (emphasis added):