Neither speaker makes this claim. Graham uses chess as one example of a human intellectual activity that is governed by fixed principles, but neither speaker says whether it’s the best example.

Neither speaker claims this. Neither Graham nor Adelaide discusses what kinds of intellectual activities are most characteristic or typical for humans to engage in.

Graham agrees with this but Adelaide disagrees, so this is the point of disagreement. Graham infers that computers can master certain human activities, meaning he thinks that this computer mastered chess. Adelaide claims that it’s the programmers’ achievement, not the computer’s.

Graham may agree with this, but Adelaide never offers an opinion. Adelaide doesn’t weigh in on the issue of machine intelligence at all, instead focusing on whether the computer or the programmers should get credit for this chess victory.

Neither speaker makes this claim. Adelaide’s argument implies that the computer was used as a chess-playing tool by its programmers, but she never generalizes that model to all principle-based activities. Graham doesn’t discuss tools at all.