ich ▁became ▁an ▁emer it us ▁professor ▁at ▁the ▁University ▁of ▁Ant werp . ▁On ▁ 2 2 ▁May ▁ 2 0 1 4 , ▁he ▁held ▁his ▁emer it us ▁lecture ▁about ▁the ▁Jewish ▁roots ▁of ▁the ▁phil os opher ▁Ludwig ▁W itt gen stein . ▁ ▁Philosoph y ▁▁ ▁By ▁September ▁ 2 0 0 4 ▁he ▁had ▁published ▁around ▁thirty ▁articles ; ▁primarily ▁about ▁language ▁( anal yt ical ) ▁philosophy , ▁in ▁particular ▁in ▁relation ▁to ▁W itt gen stein , ▁and ▁about ▁philosophy ▁of ▁mind . ▁Many ▁of ▁his ▁publications ▁focus ▁on ▁the ▁problem ▁of ▁the ▁free ▁will . ▁ ▁Le il ich ▁has ▁de alt ▁with ▁the ▁question ▁of ▁the ▁rational ity ▁of ▁p rag m atic ▁explan atory ▁frameworks ▁for ▁the ▁use ▁of ▁words . ▁As ▁such , ▁he ▁discovered ▁that ▁this ▁ability ▁for ▁humans ▁to ▁justify ▁the ▁use ▁of ▁language , ▁with ▁regards ▁to ▁its ▁norm ative ▁aspect , ▁is ▁a ▁fundamental ▁expression ▁of ▁human ▁reason ab len ess . ▁ ▁Le il ich ▁has ▁argued ▁that ▁nature ▁is ▁neither ▁evil ▁nor ▁good , ▁since ▁moral ▁pro clam ations ▁require ▁the ▁invol vement ▁of ▁mind ▁to ▁be ▁appropriate . ▁ ▁He ▁has ▁also ▁been ▁noted ▁for ▁making ▁practical ▁assert ions ▁as ▁to ▁what ▁philosophy ▁can ▁mean ▁to ▁society , ▁drawing ▁upon ▁the ▁ideas ▁of ▁Peter ▁B ieri , ▁and ▁has ▁reflected ▁upon ▁the ▁ar ising ▁of ▁new ▁branches ▁of ▁science ▁during ▁popular izing ▁lecture ▁series . ▁ ▁Further ▁more ▁he ▁has ▁investig ated ▁the ▁mental