Frithjof Schuon (1907-1998) is perhaps the most formidable modern perennialist philosopher. In his books, his poetry and his art, we find a man out of time - which is to say he lived in a world of timeless - and time-honored - spiritual ideas and principles. The scope of Schuon's insight may be compared to two of his own favorite philosophers: Plato and shrI shaMkarAcArya.
There have been numerous other brilliant modern philosophers. Yet all of them have been noticeably influenced in their ponderings by temporal changes. Were Schuon took note of such changes, and then boldly rejected them, many others have used such changes as a foundation for presenting innovations alongside any time-honored wisdom.
Here is a brief video in which Mr. Schuon is asked about the essentials of his philosophy. In this case, his philosophy is nothing less than the universal wisdom of the ages.