But weirdly, hardy anyone had scientifically investigated this, until a truly extraordinary person I got to know, named professor Tim Kasser, who's at Knox College in Illinois, and he's been researching this for about 30 years now.
Anehnya, jarang ada yang menelitinya secara ilmiah, sampai seseorang luar biasa bernama profesor Tim Kasser di Knox College, Illinois, yang sudah menelitinya selama 30 tahun.