a group g is said to be a (pf)c-group or to have polycyclic-by-finite conjugacy classes, if g/c_{g}(x^{g}) is a polycyclic-by-finite group for all xin g. this is a generalization of the familiar property of being an fc-group. de falco et al. (respectively, de giovanni and trombetti) studied groups whose proper subgroups of infinite rank have finite (respectively, polycyclic) conjugacy classes. ...

the concept of “infinite essence” that is both philosophically and theologically important, has passed many different evolutions in western history of thought. presocratics has evaluated it in two different ways. anaximender and melissus agree that the principle substance is infinite and divine, but neither absolutly transcendent nor anthropomorphic. the infinite is the fusis in its substantial...