E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Vis Iner’tiæ.
That property of matter which makes it resist any change. Thus it is hard to set in motion what is still, or to stop what is in motion. Figuratively, it applies to that unwillingness of change which makes men “rather bear the ills they have than fly to others they know not of.”
