: "Thales and the Stoics, and those after them, thought that the earth is spherical.<br/><br/>Shouldn't it be "was" instead of "is"?<br/><br/><a href='https://www.google.ca/search?q=%22thought+that+the+earth+is+spherical%22&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a#q=%22thought+that+the+earth+is+spherical%22&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&hl=en&tbo=u&tbm=bks&source=og&sa=N&tab=wp&ei=PDJzT-CLLcbd8AOPtNAk&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=2c9730b81fe4946&biw=1355&bih=913' target='_blank' rel='nofollow'>https://www.google.ca/search?q=%22thought+that+the+earth+is+spherical%22&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a#q=%22thought+that+the+earth+is+spherical%22&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&um=1&ie=UTF-8&hl=en&tbo=u&tbm=bks&source=og&sa=N&tab=wp&ei=PDJzT-CLLcbd8AOPtNAk&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=2c9730b81fe4946&biw=1355&bih=913</a>