I respectfully disagree: consensus is not an important building block of the scientific method. Also: it is generally held that someone who has completed a PhD

I respectfully disagree: consensus is not an important building block of the scientific method. Also: it is generally held that someone who has completed a PhD in physics is an expert in their small aspect of physics, and that they understand well a broader aspect of physics. Getting a PhD takes a lot less than a lifetime (fortunately).