the old guard is often scornful of newer views
How true. In fact, the old guard is always scornful of the newer view. That's why they are "the old guard".

The truth doesn't require any "guarding", least of all by those who have become overly-attached to it by reason of custom rather than acuity.

And just as there are cycles of "bunk", ushered in when a verity like the flat earth sinks like a ship over the horizon, so also there are cycles of virtue when vices become virtues and virtues become vices again.

Take greed, for instance. Thursday's Wall Street Journal carries this headline on the first page. "How Decade of Greed Undid the Proud Respectability of a Very Old Professional". And guess what, they're not talking about the world's oldest profession. They're talking about the Enron auditors who approved the Balance Sheet shell game that turned massive losses into spectacular profits, leading to the largest collapse in corporate history.

I thought greed was supposed to be good for us. Sometimes greed doesn't trickle down. It thunders down.