Lama Ole Nydahl in his book 'The Way Things Are' mentioned that Buddhism is the Way of Life, similar to Psychology, Philosophy & Religion - with certain differencies from these, however.
Modern words of HH Buddha Karmapa however explain that Buddhism is the Way of Life similar to Science, not a Philosophy nor Religion.
It's also Lama Ole Nydahl's words that Buddhism has different lessons for different people - all leading to Liberation (all of Buddhism) and Enlightenment (Mahayana Buddhism & Vajrayana Buddhism). Some people are content with Liberation only.
i think that different lessons are for different times & nations, for different religious, cultural & social groups as well.
Can someone be both Catholic (or a member of other Religion) & a Buddhist at the same time?
i understood - by HH Buddha Karmapa's words - that it's possible.
Hope others will benefit from this as well.