A time-honored rule is to comment on the idea, not the
persons or groups who might be expressing the idea.
Examples:
1+) The notion XXX is unhelpful.
1-) Anybody who believes XXX is an idiot.
... Nobody is dumb enough to believe XXX.
Sometimes it is necessary to comment on what a person
_did_. But that should not escalate to commenting on
what a person _is_. Maybe there is a Higher Power who
can look inside people and judge what they truly _are_,
but I cannot. I can only see their external acts, and
will comment only on those.
2+) The paper by A.E. Newman contains a number of
errors.
2-) Prof. Newman is too stupid to solve one linear
equation in one unknown.
There are some people who seem to live by the rule
If you don't want to be ridiculed,
stop saying ridiculous things.
... which contains a partial truth, but misses a
couple of larger points. One problem is that all
of us say ridiculous things from time to time. Also,
just because an idea can be ridiculed doesn't always
mean it should be.