What is the full quote of “Power corrupts”?
Usually quotedPower corrupts.
ActuallyPower tends to corrupt, and absolute power corrupts absolutely.
Lord Acton · Letter to Bishop Mandell Creighton, 5 April 1887
The fuller version is genuine — and the two dropped words carry the whole argument.
Almost everyone quotes the first three words and stops. Acton did not write that power corrupts; he wrote that power *tends* to corrupt. It is a claim about probability and pressure, not about inevitability, and the difference decides whether the sentence is an observation or a fatalism.
The line continues past its famous half, too. Acton goes on to say that great men are almost always bad men, even when they exercise influence rather than authority — a considerably harsher thought than the tidy epigram most people carry around.
Restoring *tends to* also restores the possibility of resistance. If power automatically corrupts, nothing can be done and no one is responsible. If it merely tends to, then institutions, scrutiny and character are exactly the things that matter — which is what Acton, a historian writing to a bishop about how history should judge popes and kings, was actually arguing about.
For your English: Hedging verbs — tends to, may, is likely to — are not weakness in English. They are precision. Learners often strip them out to sound confident and end up sounding careless instead.