what kind of paper is the hardest to slice? Newspaper? Phone book sheets?
Damp tissue?
The different papers would attest to different levels of sharpness.
Once you get good at cutting through (remember, not a slicing movement) regular 20# bond paper move up to a cash register receipt. (20# pound bond is the weight of most envelopes and office/copier paper.)
jtk
"A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
- Sir Winston Churchill (1874-1965)