It’s perhaps easier to spot little value thoughts:

• Rewind the past just for the sake of it.
• Imagine the future just for the sake of it.
• Self-imaging / glorifying yourself. Either via the past or the future.
• Repeating problems with no possible actions.
• Einsteulilung
  • Repetitive thoughts with now new insights
  • It could be an intractable problem Dealing with nebulous problems
• Problems not in your control

How to escape the doom train of thought:

• Inner stillness (one of the two methods, which is the “inside” view and the “outside/para..something” view.)

Probably valuable thoughts:

• Possibly lead to either actions or new understanding.
• Examples:
  • Consolidating/reciting/formulating what you learned recently. The problem might lying in the discipline to let the worthless thoughts slide. Trust yourself in knowing what worth to think about.

References

Steve Jobs on Signal