Full Idea
Liberty, equality and practical human sympathy are the only effective barriers we can oppose to the anti-social instincts of certain among us.
Gist of Idea
Only liberty, equality and sympathy can stand up to anti-social people
Source
Peter (Pyotr) Kropotkin (Law and Authority [1886], 1 'Anarchism'), quoted by Jonathan Wolff - An Introduction to Political Philosophy (Rev)
Book Reference
Wolff,Jonathan: 'An Introduction to Political Philosophy (Rev)' [OUP 2006], p.29
A Reaction
One might state it more succinctly as 'only the social can oppose the anti-social'. The dominance in society of essentially anti-social people seems to have become a major political fact in 2017, in the UK and the USA.