Thoughts mainly mature in exchange with other people. Most of the articles on deep-thought.org are therefore open to votings and comments from readers. We would be delighted if many of our readers would make active use of this opportunity. However, we reserve the right to delete offensive or off-topic comments.

Feedback ((c) AdobeStock)In case you can provide an alternative solution to one of the enigmas or if you want to suggest a new problem that we should deal with, please send an e-mail to This email address is being protected from spambots. You need JavaScript enabled to view it.. The presentation of a solution or problem should be similar to the existing texts and approximately one page long; additional information can be provided as a PDF file or links.

We are also looking for new members for our editorial team. If you could imagine enriching the editorial team with your skills, please send us an e-mail. Your application should include a letter of motivation explaining why you would like to work with us and what you can bring to the editorial team, as well as a CV.