The main task of the professional economist now consists, either in obtaining a wide knowledge of relevant facts and exercising skill in the application of economic principles to them, or in expounding the elements of his method in a lucid, accurate and illuminating way, so that, through his instruction, the number of those who can think for themselves may be increased.

<Luc, lum, lus> (light): (1) lucid, translucent, luminous, illuminate, luminary, luster, illustrate, illustrious; (2) lucent, Lucifer, lucubration, elucidate, pellucid, relume, limn.