Deceptive Happy Thoughts

Planning your future requires some imagination, but that imagination is under strict control by your rational thoughts. When someone asked you plan out your next 5 years on a sheet of paper, you wouldn't write how you'll accomplish great feats in all sorts of endeavors. Instead we make plans rationally and realistically: what fields of your life could you improve and what goals will you set to obtain improvement.

So we write out a long plan of how, when and how you'll end up. You'll read it out loud and it seems reasonable.
Yet there are those other thoughts...

You hear a great song and suddenly you've daydreamed for 5 minutes about being a successful musician although you know it's a goal not worth pursuing. You'll never get those 5 minutes back and your is now better at daydreaming, so next time you might go 6 minutes. This is how our minds work when don't think about our thoughts.

There are also other drawbacks to this awful habit. First and foremost, you could have spent that time thinking about something useful. Secondly, something I have noticed myself quite a lot, when you daydream about something that's more personal to you and you snap back to reality and realize you don't have and likely never will have the life you dreamed about, it can be cause enough for a depressive episode.

We shape the world with our thoughts.
As longs as we don't seriously decided what we choose to think about, our lives will reflect that.