A man who does not care whether he votes is not likely to care much which way he votes; and he who is in that state of mind has no moral right to vote at all
 John Stuart Mill, Considerations on Representative Government (1861). copy citation

Context

“The voter who does not care enough about the election to go to the poll is the very man who, if he can vote without that small trouble, will give his vote to the first person who asks for it, or on the most trifling or frivolous inducement. A man who does not care whether he votes is not likely to care much which way he votes; and he who is in that state of mind has no moral right to vote at all; since, if he does so, a vote which is not the expression of a conviction, counts for as much, and goes as far in determining the result as one which represents the thoughts and purposes of a life."—Thoughts, etc., p.” source