This English expression is commonly used in both written and spoken language as a metaphor rather than in a literal sense.
The expression is used to denote that someone does not want to make a choice between two things and thus is remaining neutral. It is often used in the context of someone being told that they have to make a decision and “stop sitting on the fence.” It can often also refer to the act of not taking of a side in an argument in order to remain on good terms with both parties.
The expression is said to date back to the Revolutionary War when a judge had not committed to either the Revolutionaries or the Loyalists. George Washington was then said to have asked one of the judge’s slaves which way he was leaning and the slave is said to have replied in saying “until my master knows which is the strongest group, he’s staying on the fence.” It is said that Washington found this reply so apt and amusing that he began using it himself and thus it came into frequent use.
An example of the usage of this expression in spoken language can be found in a quote by previous Chancellor of the Exchequer David Lloyd George; “he has sat on the fence so long that the iron has entered his soul.”