I know. You just came back from work and you're tired and you even had enough willpower to go to the gym and now you're really really tired.

Can I sleep? Can i just do it tomorrow? I’ve done a lot of work today already...

Well I’m no psychic but I’ll try to predict your future.

Tomorrow evening you’re going to come home tired. Then you’re going to say something like:

Can I sleep? Can I just do it tomorrow? I’ve done a lot of work today already...

They say tomorrow never comes. The real problem is that tomorrow always comes, and you assume it's going to keep coming.

Tomorrow can stop coming whenever it wants. And you can start whenever you want.

Why not now?