# Why do we have a trust tag?

The tag appears to have been introduced in the past two months and has now been applied to three questions with no common theme that I can discern besides the use of the word ‘trust’:

There is no usage guidance or tag wiki.

Does the tag actually serve a useful organizational purpose, or can we remove it?

• I thought the same thing as I added the "trust" tag to the last question you listed above. – Patriot Sep 15 at 4:52
• I removed the trust tag from all questions that had it today. – Squeamish Ossifrage Sep 28 at 14:48

## 3 Answers

The word ‘trust’ is too vague and general to serve any purpose in the lexicon of the field. Its useful role is limited, at best, to the pithy substitution ‘be vulnerable to’. There is no meaningful common theme to the three questions and the tag serves no useful organizational purpose.

Remove the tag.

is a concept in security, but it's rather vague. I think it's warranted on Security, which habitually deals with such higher-level concepts, but on Cryptography, we need more precise tags. As I write, there are 7 questions with this tag, and I can't see a unifying theme:

Conclusion: we should manually get rid of the tag, in some cases by replacing it with a more appropriate tag.

Trust is a salient concept in cryptography, increasingly discussed: zero trust, Web of Trust, trusted platform module, trusted server, trusted messenger, trusted protocol, trusted key, trusted third party, etc.

Even if we define trust within the bounds of what we think is likely or possible, or if we base trust upon strict rules to give it weight, trust will still depend on assumptions. Trust is involved in all things human, even in the application of perfect security.

We cannot formalize trust, but we can make it reasonable and give it weight--that is what expertise in cryptography is generally for. Trust is always going to be based upon assumptions, but at least we can make this clear, identify those assumptions, and use this understanding to justify trust based upon expert cryptographic knowledge. Trust as a reasonable judgment based upon a set of assumptions serves a useful purpose in cryptography.

Keep the trust tag and provide usage guidance.