"Evil is a make-believe concept we've invented to deal with the complexities of fellow humans."An idealistic young American couple was killed in an Islamic State-claimed terrorist attack last month while on a cycling trip around the world.Jay Austin and Lauren Geoghegan, who were both in their late 20s, last year quit their office jobs in Washington, DC, to embark on the journey. Austin, a vegan who worked for the US Department of Housing and Urban Development, and Geoghegan, a vegetarian who worked in the Georgetown University admissions office, decided that they're were wasting their lives working.The couple documented their year-long journey on ​Instagram and on a ​joint blog. As The New York Times ​put it, they shared "the openheartedness they wanted to embody and the acts of kindness reciprocated by strangers."“You read the papers and you’re led to believe that the world is a big, scary place," Austin wrote.However, Austin and Geoghegan's dream trip came to a tragic and gruesome end when they got to Tajikistan, a country with a known terrorist presence. They were riding their bikes through the country on July 29 when a car rammed them, ​​according to CBS News. Five men got out of the car and stabbed the couple to death along with two other cyclists, one from Switzerland and the other from the Netherlands.