"Get on the train! Be on the train!" - I'm always saying this. But what does it really mean?
To me, being on the train means that you are sensitive to the energy of the other person - be it nage or uke. You "go with the flow" rather than try oppose the other person's power. This is not only safer (you won’t be taken unexpectedly if someone suddenly tries to do a technique) but it is also more effective.
However, I have practised with some people who take a different view of being on the train. I remember one teacher who shall remain nameless (mainly because I’ve forgotten his name!) who insisted that being on the train meant that the uke should fall over when the teacher did a technique. If you ended up just standing there, he would ‘correct’ you – “Oh no, you are not on the train. If you’d been on the train my technique would have worked.”
Well, pardon me for taking issue with that. But I am not of the opinion that it is the uke’s job to make a technique work!
Anyway, here is a passage taken from Koichi Tohei’s book (‘the black book’) on Aikido:
“Not to receive anything means unlimited strength. If you try to stop with your strength a train which is coming toward you, you will be flung aside though you may have very great strength. It is better for you to ride on the train, and when it stops you take one step forward and get off.
“Though your opponent may be strong, if you do not struggle against his strength but follow it and when it stops you go one step ahead of him, you will be able to lead him to fall down.”
And that, in my view, pretty much sums up the essence of the art of Aikido.