Battles of Educational Theories

In the Blog post, "Out and About: Discussion on Educational Schools of Thought" http://www.uleduneering.com/kappnotes/index.php/2007/01/out-and-about-discussion-on-educational/ there is an interesting conversation being held by multiple educational minds and in this conversation the concept of the various educational theories is addressed. In this conversation, the speakers agree that there are various "isms" in education and that maybe the best school of thought is to utilize/employ the best of each of these theories instead of one or the other. I definitely agree with this idea for there are numerous ways to learn and to exclude completely any educational theory would be shortsighted. As mentioned in the original blog, learning encompasses many aspects therefore it makes sense that multiple theories should be incorporated in the learning process. I also think the division of the major theories into learning appropriate ages was well done too. Behaviorism definitely seems best applicable to a younger learner while cognitivism seems to fit a young adult learner, leaving constructivism to be the best approach for older/adult learners. The only issue I have with this post, isn't really an issue but a question/idea to pose. Undoubtedly there are numerous theories in education and each theory can overlap in ideas while still having offering something useful. However, I do feel there are some theories which possess contradictory approaches or elements. Bearing this in mind, how does one decide which parts of each theory to use in the education process when some of those theories have contradictory components.