Difficulty of theorem?

[tgt]

How can we rank and compare the difficulty of theorems in different fields?

[cristo]

Why would one need to?

[tgt]

Why would one need to?

Don't know but one might find it interesting to do so and wonders how?

[Crosson]

The answer is that every actively researched field has theorems of any desired difficulty i.e. for all fields of research F and for all levels of difficulty D there is at least one theorem T in F such that the difficulty of F is greater then D.