James M. Landis, Dean of the Law School in the Guardian lecture over station WEEI last night discussed Liberty As An Evolutionary Idea. Conceptions of liberty, he contended, must be allowed to change with economic conditions. Some pertinent excerpts from his speech follow:

"Instead of a philosophy that rests upon the belief that only good could come from the absence of restraint and that the essence of freedom lies in that fact, today's society seems to build upon a faith that it is the function of our economy to assure certain minimum claims to individuals.

"Our difficulty today, perhaps an individual one, is that the content and limitations of the newer rights are still obscure. The old pattern is thus broken but the new has yet to crystallize. And so we stand in hesitancy and doubt, conscious that we cannot and must not recreate the old, yet fearful of the new.

"The rivers of our national life will flow onward and not backward. Change as such one need not fear. It is the temper in which changes are born that matters. That temper implies a readiness to recognize the claims of others to civilized living, a willingness to submit the means for the attainment of that end to the traditional methods of discussion and debate, and an avowal so to arrange our institutional life as to make it realize, so far as humanly possible, the content of the new and growing liberty."