Commonly Confused Expressions: "On the contrary" vs. "In contrast"

So what's the difference between "on the contrary" and "in contrast"?

I often encounter people who keep saying "on the contrary" when they should be saying "in contrast".

There's a simple way of checking whether or not you should say "on the contrary" -- you can replace the expression with "That's wrong." If it still makes sense, then you're using it correctly.

For example,

(1)

They looked like the ideal couple. Everybody believed they were happy. On the contrary, they were actually miserable and heading for a divorce.

They looked like the ideal couple. Everybody believed they were happy. The impression was wrong. / That was wrong. They were actually miserable and heading for a divorce.

(Here, the idea is still intact.)

(2)

His father is a very diligent worker. On the contrary, the son is a slacker who likes doing nothing.

His father is a very diligent worker. That's wrong. The son is a slacker who likes doing nothing.

(Does it) Make sense? No, not really. In this instance, it's proper to use the expression "in contrast" --

His father is a very diligent worker. In contrast, the son is a slacker* who likes doing nothing.

(A slacker is a lazy person who frequently or habitually avoids work.*)

Here, we're comparing -- i.e. contrasting -- two different individuals, so we use "in contrast". When we use the expression "on the contrary", we're often disproving a concept, a belief, an opinion, etc.

How about the expression "to the contrary"?

Merriam-Webster Online defines it as "on the contrary" (probably because the meanings are similar) but there's a difference in usage. Normally, we use "On the contrary" to introduce the opposite idea, something which disproves a previously stated belief or opinion (or sometimes even a statistic).

Most people think they are extremely serious. On the contrary, they have a rather childishly playful sense of humor.

When we use "To the contrary", we don't normally disprove a previously stated belief or concept -- that is to say, the expression is not preceded by a statement which it aims to debunk or disprove.

"To the contrary" collocates with words like "evidence" or "convince"

You will waste your time trying to explain and prove your innocence. He is convinced to the contrary. He believes you're guilty.

She has already almost persuaded me of her being warmly attached to her daughter, though I have been so long convinced to the contrary. (This is a quote from Jane Austen's Lady Susan.) -- The speaker doesn't believe the mother has a warm relationship with her daughter. (The mother has been trying to convince the speaker that she does.)

Unless you can give me evidence to the contrary, I have to believe he is telling the truth.

Unless you can give me evidence which tells me otherwise, I have to believe he is telling the truth.

(To simplify further -- )

Unless you can give me evidence which tells me the opposite, I have to believe he is telling me the truth. (Unless you can give me evidence that he's lying, I have to believe he is telling me the truth.)

Hope the explanations help. 

Until next time!

M.