If you aren't a regular reader of Paul Wells, check out his blog today.
He points out the fiscal impact of the corporate tax cuts that Jack Layton is making the price for his support of the Liberal government and its budget.
As Paul says at the end of his blog post, "Draw your own conclusions about what that means. My minimal point is that we have these national debates with incredibly high political stakes and you so rarely see anyone pause to explain the relative scale of things."
Perspective matters.
Another word for it is "context".