Eclecticism is the philosophical practice of selecting the philosophical doctrines that to them, seems to be the most reasonable. These practices constructed a new system of beliefs, generally called Eclecticism. It's truely a democratic way of approaching philosophy. As a result, to Eclectics, the whole of Greek (or Hellene) Philosophy smorgasbord where they can pick and choose what they want and leave the rest. Stoicism was aescetic in it's approach, and Epicureanism was hedonist in it's approach as both were extremes. Skepticism had denied that pure Truth can be attained (Real World skeptics still do that). Eclectics believed by selecting what doctrines they believed in, they can attain the highest Truth.
If there was a class that could cast Divine Magic without domains and without being a druid or paladin, then a PC that takes that class would be an Eclectic Philosopher. But not all Eclectics are divine spellcasters. Some are psychics, some are warriors, and some are wizards. Eclectic philosophy is probably a reaction to the many philosophies that abounded during the Golden Age of the practice.