
“The strongest argument proves nothing so long as the conclusions are not verified by experience.”
[H]aec vocatur scientia experimentalis, quae negligit argumenta, quoniam non certificant, quantumcunque sint fortia, nisi simul adsit experientia conclusionis. Et ideo haec docet experiri conclusiones nobiles omnium scientiarum, quae in aliis scientiis aut probantur per argumenta, aut investigantur per experientias naturales et imperfectas...
OQHI, 43 http://www.mlat.uzh.ch/MLS/text.php?tabelle=Rogerus_Baco_cps4&rumpfid=Rogerus_Baco_cps4,%20Opus%20tertium,%20%2013&level=3&corpus=4&lang=0¤t_title=Opus%20tertium&links=&inframe=1&hide_apparatus= as cited in: James J. Walsch (1911) """"Science at the Medieval Universities"""" in: Popular Science, May 1911, p. 449 http://en.wikisource.org/wiki/Page:Popular_Science_Monthly_Volume_78.djvu/459
Opus Tertium, c. 1267
Context: The strongest argument proves nothing so long as the conclusions are not verified by experience. Experimental science is the queen of sciences, and the goal of all speculation.