Sidney Hook. a distinguished and liberal professor of philosophy. to present a paper on the thesis that there are no national truths in science. that there are no such things as class truths or party truths. and that the entire cause of international scientific cooperation and peace has been undermined by the doctrine that there are these national or class. or party truths. Although Dr. Hooks request was sponsored by Dr. Anton J. Carlson. famous physiologist and former president of the American Association of University Professors. Dr. Hook was still denied a hearing. As Miss Dorothy Thompson puts it: The upholders of free speech and free scientific inquiry are kicked out by the persecutors of both. * * * Now that the Department has issued the visas. it owes something to American upholders of free speech. namely. insistence that all sides should be heardnot in a rival conference. but in this one.