Can a Catholic follow a philosopher other than Aquinas? The answer is that it depends! Some philosophies teach false doctrines that are opposed to the faith. However, there are, of course, great Catholic thinkers too.
What should a Catholic think about Aquinas as opposed to other Catholic philosophers?
(Credit goes to one of my mentors Dr. Ralph McInerny (RIP) for helping me think this through.)
Get the St. Thomas Aquinas On The Morality Of War And Killing program available here.