William Shakespeare önce said "The web ofour life is of a mingled yarn, good and ili together." 400 years later, this observation proved to be more correct than ever. The twentietk century saw more momentous change than any previous century: changefor better, changefor worse; change that brought enormous benefit to human beigns, change that threatens the very existence ofthe human species. Manyfactors contributed to this change but in my opinion the most important factor was the progress in [technology].