In the poem "If" by Kipling, the speaker states that we should treat the two imposters the same:
If you can meet with triumph and disaster
And treat those two imposters just the same;
The speaker is stating that triumph and disaster are the both imposters. This means that triumph may not be a victorious moment in which to celebrate. Hitler was triumphant, but his victory was really a disaster. In this way of looking at triumph, it is easy to see that Hitler's triumphant victory was an imposter. He celebrated a horrible event. Ultimately, his triumph changed to defeat. When the Americans moved in on his soldiers, he lost the battle and ended his life in suicide.
Disaster can be determined an imposter as well. When something tragic is turned around for good, the end result can be a blessing (Romans: 8:28). Suppose a person loses his home in fire, the second home can be built much nicer and more spacious. This terrible beginning can have a happy ending. In this way, disaster can be turned into a blessing.
What the speaker is saying is that the reader should be careful in his or her interpretation of any event. What appears to be a triumph can really be a disaster, and what appears to be a disaster can really be a blessing. Therefore, the speaker's suggestion is to treat both triumph and disaster the same. It is up to the reader to interpret both imposters for what they are.