Investing: short / long term asset allocation in which you feel comfortable and ALLOW YOU TO SLEEP WELL at night.
Speculating: short / long term asset allocation in which you feel comfortable but DOES NOT ALLOW TO SLEEP WELL at night.

I dont try to make a theoretical distinction, because PERSONAL paradigms come to play, and debate will continuous, with no future end.
Is like the psychological question: What is right or wrong ?, depends on personal paradigms and believes. What is ok for you, I can perfectly find it wrong.
If you know the odd of wining, you aren't speculating or investing, for sure, you will be rich in the future. But this does not happen in real life. So, lets come back to reality, and try to survive in the cannibal jungle of finance.