Full Idea
Since, by definition, nothing happens in a temporal vacuum, there is no possible means of determining its length.
Gist of Idea
Since nothing occurs in a temporal vacuum, there is no way to measure its length
Source
Robin Le Poidevin (Travels in Four Dimensions [2003], 02 'without change')
Book Reference
Le Poidevin,Robin: 'Travels in Four Dimensions' [OUP 2003], p.22
A Reaction
This is offered a part of a dubious proof that a temporal vacuum is impossible. I like Shoemaker's three worlds thought experiment, which tests this idea to the limit.
Related Idea
Idea 8595 If three regions freeze every 3rd, 4th and 5th year, they all freeze together every 60 years [Shoemaker]