MONEY (Lat. moner­is; from Gr. μόναρχος), a cat­e­go­ry of ob­ject whose val­ue de­rives from that for which it may be ex­changed, and be­ing val­ue­less oth­er­wise.

Although that seems para­dox­i­cal, any cur­ren­cy of non­triv­ial in­trin­sic val­ue ul­ti­mate­ly suc­cumbs to what is com­mon­ly called Gre­sham's Law: the ob­ser­va­tion that com­merce prefers the most de­based cur­ren­cy avail­able. For ex­am­ple, sup­pose you have both a sil­ver quar­ter mint­ed in 1960 and a chromed plas­tic quar­ter mint­ed in the present day. De­spite the two coins hav­ing the same nom­i­nal val­ue of twen­ty-five cents, you will nev­er­the­less hoard the sil­ver quar­ter due to its greater com­mod­i­ty val­ue, with the cu­mu­la­tive con­se­quence of driv­ing all sil­ver quar­ters out of cir­cu­la­tion.

Money which fails to cir­cu­late ef­fec­tive­ly los­es its nu­mis­mat­ic func­tion and be­comes a mere good: some­thing whose val­ue is reck­oned by some oth­er de­nom­i­na­tor than it­self. It there­by fol­lows that the ide­al cur­ren­cy (the cur­ren­cy that cir­cu­lates most ef­fi­cient­ly) is that which is in­trin­si­cal­ly worth­less, yet trans­ac­tion­al­ly vi­able.