View > Dock Icon has two CPU choices:
- Show CPU Activity
- Show CPU History
I am on a dual core (MacBook Air (13-inch, Early 2014). In both views, I see 4 items.
Using High Sierra.
While researching the Activity Monitor, I saw this:
Relatively speaking, I'm less familiar with hyper-threading than older CPU technology, so I'm putting this in an answer, and letting the community vote.