Medieval philosophy is the philosophy of Western Europe from about 400–1400 AD, roughly the period between the fall of Rome and the Renaissance. Medieval philosophers are the historical successors of the philosophers of antiquity, but they are in fact only tenuously connected with them.
Until about 1125, medieval thinkers had access to only a few texts of ancient Greek philosophy (most importantly a portion of Aristotle’s logic). This limitation accounts for the special attention medieval philosophers give to logic and philosophy of language. They gained some acquaintance with other Greek philosophical forms (particularly those of later Platonism) indirectly through the writings of Latin authors such as Augustine and Boethius. These Christian thinkers left an enduring legacy of Platonistic metaphysical and theological speculation.
Beginning about 1125, the influx into Western Europe of the first Latin translations of the remaining works of Aristotle transformed medieval thought dramatically. The philosophical discussions and disputes of the thirteenth and fourteenth centuries record later medieval thinkers’ sustained efforts to understand the new Aristotelian material and assimilate it into a unified philosophical system (from Routledge Encyclopedia of Philosophy).
Medieval names sometimes create a challenge. Even more than with ancient names, you may run into variations on a name between texts, as, besides the official Latin document name, a person would have a name in the local language or dialect; if famous, there might even be a third name by which the person was known in foreign lands. Again, bibliographic listings, and the way the name is entered in a library catalog or a periodical index, as well as in the indexing for Google and other search engines may vary. Here are some things to keep in mind:
You may have to use exact forms of the name, even though the 'incorrect' name as keyword may still pull up a number of hits. The most popular names (Dante, Petrarch, Abelard) will be the easiest, but be careful when you see more complicated names. Try to analyze and see if any part of the name is an honorific or a geographic descriptor instead of the name itself, so you can put it in correctly as a subject heading. You can also search the variations as keywords with OR as the operator; e.g. "Abelard* or Abailard".