Is a religion based on philosophy possible, or could a ready-made school of philosophy like Epicureanism form a basis for a modern religion too? Could Epicureanism even be used as it already was, and just be revived in a modern world?
The difficult part for me at least would be how to avoid creating another strictly dogmatic belief-system. In fact, in the tradition of Bertrand Russell or Karl Popper I do see dogmatism as one of the gravest dangers that can threaten the human kind.
All modern religions are mostly collections of dogmas. On the other hand, a religion is of no use if its ideas are not taken seriously enough. This is the main reason why the core ideas are given the position of dogma in a religion. Epicureanism was a religion-like system already 2400 years ago. It had its own dogmas in the form of the 40 Principal Doctrines, as we call them. These 40 wise sayings form a neat and extremely useful package of moral and ethical guidelines.

On the other hand, nobody follows to the letter all dogmas of any religion. The reborn modern Epicureanism could be used in a similar way. Adherents would claim to follow the whole program of high ideals. However, in the real world they would implement only the parts that they are capable of. This naturally happens with all religions all the time.
Atheism, agnosticism and free-thinking in general are just rejections of religious dogmas, but Epicureanism could be used as a positive force. It includes strong moral basic guidelines. Epicureanism can really make people look at their way of life, their actions and behavior from a new angle.

Epicureanism is also part of the great Greek humanistic tradition. Many of the modern humanistic ideals are already embedded in Epicureanism. However, I personally am not a pure Epicurean anymore. I started out as a full-fledged Epicurean. However, when I found Marcus Aurelius I encountered a positive, strongly humanistic world full of hope, but also deep realism on how the world goes.
Oh yes, even if I am the admin of the Garden Of Epicurus in Facebook and the main Facebook-page for Epicurus himself, I am more of a Epicurean Stoic nowadays!
I am also the admin of the main fan-page in Facebook for Marcus Aurelius also at http://www.facebook.com/pages/Marcus-Aurelius/123395559393

Marcus Aurelius - Wikipedia

Mixing the extremely rational moral and ethical teachings of Epicurus with the deeply humanistic view on humanity of Marcus Aurelius does produce for me at least a complete system of thought. In fact, the combination is much fuller and rewarding than either of these men can offer individually.
The impact of deep humanism of Marcus does soften the often quite strong ethical and moral demands that are embedded Epicurean thought. On the other hand, the rational analysis of human behavior of Epicurus does compliment the at times rather romantic ideas of Marcus Aurelius. Of the other Stoics, I find only Epictetus as noteworthy, but Marcus Aurelius is the real jewel of the Stoic tradition for me.

A simple competition for market-share was one of the reasons why Stoics and Epicureans were at odds in Greece and Rome of Antiquity. However, we do not need even to notice such a thing anymore. There were also some deeper ideological differences, but I must admit that they have never bothered me at all.
The idea of a ‘god’ is for Marcus Aurelius just a Deistic original quite cause, quite like the Einsteins pantheistic idea of the whole entity of nature as a ‘god’. However, the god of Marcus Aurelius does bear no relationship to the angry father-figure of the Judaic or Christian tradition. It just happens that they call their vengeful god-figure with the same name   that Marcus Aurelius uses for his utterly different idea of a pantheistic universal ‘spirit of nature’

The ‘god’ of Marcus Aurelius does not affect human lives in any way. It does not act in any kind of supernatural way either. Marcus Aurelius thought that humans themselves do make the decisions that mold and change their lives. They can never rely on any kind of deities to help them. In this he is quite in sync with Epicurus.
Epicurus had also ideas of gods as perfect role-models for humans to imitate. These Epicurean ideals did not have any kind of influence on human life. Either Aurelian or Epicurean systems of ideas do not need the idea of god at all to work. Among the modern Stoics even majority are either agnostics or atheists. Yes, there are modern Stoics all over the world. See http://newstoa.com/

Like so many followers of philosophy, I have built a personal philosophy that collects wisdom from different, but selected and mutually compatible sources. My own philosophy includes the best parts of both of Stoicism and Epicureanism.
However, they are modernized with a help with a good mix of Karl Popper's views on science and Bertrand Russell's views on society and most of all global human solidarity.

Bertrand Russell - Wikipedia

In fact, I think that private, one-man philosophical systems like the one I described above are a quite common occurrence. An openly thinking person ends up picking and choosing the best parts from religions and teachings of the best of philosophers. He or she then connects them in his of or her mind to form a coherent view of the world that often does work for them just like a religion is supposed to work; as a base of support and comfort.
They just do not call their own collections and mixtures of ideas ‘religions’ and they even can well follow the outward rituals of an existing religion.

My page for Karl Popper is in Facebook at:
http://www.facebook.com/popperphilosopher
My page for Bertrand Russell is in Facebook at:
http://www.facebook.com/russellbertie

(This piece was refurbished on 21th of April, 2013)