For people who live in the knowledge society which has rapidly been changing, learning in the widest sense becomes indispensable in all phases of working, living and playing. The construction of an environment, to meet the demands of people who need to acquire new knowledge and skills as the need arises, and enlighten each other regularly, is becoming very important. Thus, we hope to make the best use of the advantages of a rich e-learning environment which aims at "anytime, anywhere and anybody" learning, because participants in lifelong learning for the knowledge society demand to learn at the right place and right time, and with learning content, they can select themselves. However, in a general e-learning environment so far, because the situation is usual in which the instructor is absent and has the asynchronous access without an immediate communication with others, the participants tend to be solitude and it is difficult to maintain the learning motivation. Therefore, the creation of a new e-learning environment becomes extremely important in which various participants can learn and enlighten each other through an occasional and helpful interaction among them in appropriate learning communities in the network environment. In this paper, we present 5 points as basic requirements for the construction of an e-learning environment which can satisfy the various learning demands of the knowledge society, and discuss how to realize them. The key point here is the extension of the usual "strong" collaborative learning to effective "weak collaborative learning". In addition, the evolution of "symbiotic learning" for the knowledge society, that is, the necessity of "symbiotic e-learning environment based on occasional collaborative relationship" and its effective realization are discussed.