I don't think it's quite so bad as that. There is the yet wider (but still limited) world of empirical evidence. It can't reach proof, but it can make use of probability. And then this can be widened out even more to all sorts of evidence (whether empirically reproducible or not). That begins to encompass a lot more things that are objective in their own right (whether empirical or not). If I'm not mistaken you and most of us here will all agree that objective truth doesn't cease to exist just because it may be beyond our empirical grasp. Just because two people make contradictory claims doesn't mean one of them can't be objectively right. It only means they both can't be right. (that last statement itself is an unprovable assertion by the way --but I'm betting all of us here handily accept it on faith alone.)
Well, I haven't read Weinberg, so I don't know what he does or doesn't have on offer. But if physicists generally have that attitude toward all philosophy, then that might explain the woeful state of philosophical understanding that so many physicists are languishing in. I guess Weinberg and/or his colleagues have fallen down on the job getting them philosophically educated, then. The result of such physicists dismissing philosophy is not that they then don't have one. It's that they then are duped into defending an embarrassingly bad one -- one that is easily dismissed by even those of us outside the profession who nevertheless prefer to keep our eyes open and not bury our heads in the philosophical sand.
I'll borrow the words (and Myers quote) from a blogger "The OFloinn" in this particular blog who shows this better than I ever could...
Myers: Whoa. Scientists everywhere are doing a spit-take at those words. Philosophers, sweet as they may be, are most definitely not the "arbiters" of the cognitive structure of science. They are more like interested spectators, running alongside the locomotive of science, playing catch-up in order to figure out what it is doing, and occasionally shouting words of advice to the engineer, who might sometimes nod in interested agreement but is more likely to shrug and ignore the wacky academics with all the longwinded discourses. Personally, I think the philosophy of science is interesting stuff, and can surprise me with insights, but science is a much more pragmatic operation that doesn't do a lot of self-reflection. [Emph. added] [[end of Myers quote]]
Socrates once said that the unexamined life is not worth living; but Myers seems to brag about the limited mental horizons he ascribes to scientists. IOW, Myers is a technician not a thinker. How do we know? Because if he had thought about it he would never have used that locomotive-of-science metaphor. If the locomotive is science, we should remember that locomotives run down tracks laid by someone else and can only go to those places to which the tracks already run. Bad, metaphor, bad! Go to your room.
But who are these philosophers Myers sees huffing and puffing alongside the engine telling its puissant Baconian engineer that facts and theories are distinct? Mere nithings, like Poincare, Mach, Einstein, and the like, who are not fit to drive P.Z. Myers' choo-choo.