עצמיות" בעבודה -- משל"

A nice משל from Rav Pinkus -- it is in the sefer שיחות ר' שמשון דוד פינקוס זצ"ל - פסח, ספירת העומר, שבועות, in the last מאמר, which is called בין הזמנים -- גילוי עצמיות האדם. I recommend/suggest reading the entire מאמר if you are able to, but I will just share part of it -- a bit of background and then the משל.
One of the main ideas of this מאמר is about making our עבודה our own -- something that R' Pinkus calls "שלנו" and "עצמיות". Hashem is יחיד, and we are supposed to emulate Hashem, so the way that we can try to be יחיד is by working on our רוחניות by ourselves and making it our own, making it a part of us. Rav Pinkus brings the following משל that he says משגיחים tell about בין הזמנים.
Let's say there's a train consisting of several cars, and you don't know which way is the front and which way is the back and where the engine/motor is located. How can you figure out where the engine is? Disconnect all the cars of the train from each other, and then see which car continues moving even when it's disconnected -- clearly that's where the engine is!
So too, a נסיון is when a person is alone, when he is not in his normal routine/schedule. In our normal routines, we know how to act, what to do, etc. But in a נסיון, in a different situation, we can't just go on "auto-pilot". The only way to act properly in such a way is if we have made our עבודה our own, if we have "עצמיות".