It is considered that Plato and Aristotle had different ideas of what art means but under all the thinking and dialogue I think they both had the same appreciation for what it is... a perfectly creative representation and connection to what makes us human.
In this line of thinking I'd like to argue that Realism and Idealism both aim to achieve the same thing. Although one may lean more towards portraying 'what is' and the other 'what should be', they both embody an approach that best tries to tell a story of the human experience through the perfection of creativity.
Basically, Realism is trying to represent a real human experience as real/perfect as possible and Idealism is trying to tell a human experience in it's ideal/perfect form. So if one is trying to portray the human experience perfectly and the other is trying to portray the perfect human experience, aren't they both actually just trying to do the same thing? Although they look different in their end result, I think you could say they both achieve the same result; a depiction of a perfectly human experience brought to life through perfectly human creativity/imagination.
(Disclaimer: this blog post is not to be taken too seriously and is to be appreciated as a piece of verbiage - a test post for the charlesfoleyart.com website. Thanks.)