Ideas get proven true or discredited and, unlike with people, it’s silly to mainly conceptualize them as “old.” For there are only two types of ideas: good ideas and bad ideas.
Or, we could say, erroneous ideas and eternal ideas.
The Founding Fathers did not say, “We hold these old ideas to be self-evident…” or even “We hold these ideas to be self-evident…,” but, “We hold these truths to be self-evident….”
A truth, properly understood, is an eternal idea. It’s not old or young because it’s not of this age or that age, but is ageless (even if it was just recognized by man 200 years ago). That microscopic organisms can cause disease was only discovered relatively recently in history, but it was always true.
Likewise, that murder (correctly defined as the unjust killing of a human being), rape and theft are wrong — and that a virtuous people’s freedom is better than tyranny — are always and everywhere true.
Speaking of confusion, Biden followed his assertion that you can’t govern a country with “ancient ideas” with the warning that they “only take us back.” Now, if we’re to use these concepts of “backwards” and “forwards” to describe civilizational change, note that “going back” is often beneficial.
Just as a sick man wants to go back to his former state of robust health, so did we want to go back to fuller employment after statist governors destroyed millions of jobs with misguided COVID lockdowns. But, of course, Biden was alluding to the notion of “progress” (and its antithesis).