Yeah. We've figured it out quite a very long ago. These are the Four Noble Truths in Buddhist teachings. Here's more info:

4. marga (Noble Eightfold Path) is the path leading to the confinement of tanha and dukkha.

The way to eliminate Dukkha is by practicing the Noble Eightfold Path. which consists of:

- Wisdom (Pañña)
  1. Right Understanding (sammä-ditthi)
  2. Right Thought (sammä-sankappa)
- Morality (Sīla)
  3. Right Speech (sammä-väcä)
  4. Righteous Deeds (sammä-kammanta)
  5. Right Seeking (sammä-ajiva)
- Concentration (Samädhi)
  6. Right Effort (sammä-väyäma)
  7. Right Mindfulness (sammä-sati)
  8. Right Concentration (sammä-samädhi)

You are welcome to learn more.