Agree with VS. Agree on/about

Question

I'm looking for the right explanation of the difference between "agree on/about something" and "agree with something."

My guess is that if we agree with something, we second someone's comment, proposal, etc. If we agree on or about something, we focus on the matter we have the same opinion about:

I entirely agree with the comments you made about public transport (I can second them).

The committee members all agree on the need for more information (the focus is on the thing they have the same opinion about - the need for more information).

I feel there is a slight difference between the prepositional phrases, but they don't mean the same thing and are not always interchangeable (although they often can be).

So, how would you explain the difference? Is my guess right? If it is, is there anything to add?

Answer 1

In many cases the two can be interchangeable with each other. For instance the following two sentences are essentially equivalent:

• "We agree with his proposal to buy new computers."
• "We agree on his proposal to buy new computers."

But there are subtle differences, and sometimes they are not interchangable.

In general, you "agree with" someone else's argument when you share their particular belief about it, or accept it as true. To say that you "agree with" someone can sometimes imply that it is their idea, and that you are accepting it as true.

Multiple individuals "agree on" an idea or concept when they all accept that this particular idea is true. This implies that everyone accepts the idea/argument, but is not implying "ownership" of the idea. As you said, it focuses more on the thing being agreed upon, rather than the person proposing the idea.