He argued that scientific knowledge has grown about "what we know the child is doing and looks like" and he claimed that we now know that fetuses are "fully human" even "very early" in gestation.[51] Stewart also defended Mississippi's claim in its briefs that new medical advances with viability were at odds with past assumptions made when formulating the viability line.[52] Also, he claimed that the understanding about when fetuses begin to feel pain has grown.[53] Stewart maintained that because of the decisions in Roe and Casey, the government is being kept from responding to these facts by prohibiting pre-viability abortions.[54]