I could accept that, however games like tetris and Harvestmoon both are practically single player without an opposing active agent, player or Computer controlled player or otherwise.
In harvest moon the entire goal is to run the most successful farm you can, get married and have children. There is no competition against active opposing agents in the game. In pure tetris one plays against nothing more than time, and placement of pieces. Once again, without an obvious opponent.
Hence why I include multi-agent. All games include more than just the player. Not always in the form of another player. It can be in the form of the enviroment itself acting as the passive opposing agent. This is why I chose the "Problem space" because all games have problems to be solved and not all games give you a single solution or even a small solution set to that problem space. Which leads to why I chose to call the player a "solution explorer".
In my case I chose the neutral term of solution in favor of victory. Victory implies, formally, a competition or battle, a head to head confrontation. Not all games fall under this categorization. So I chose, implicitly, through my purposed definition to place competitions and conflicts as sub-elements to games.
Once again this is where Solitaire is a good example.
Though I appreciate the effort, Infy, and your contribution helps to carve out the mold through deduction.
One does not have to be a scientist to understand, or study science. Likewise one does not have to be a gamer to understand, or study games.

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There are no truths in science, only the falsifiable hypotheses and explanations of the people who test them.
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