Problem: Each team consists of a maximum of eleven players (excluding substitutes), one of whom must be the goalkeeper. Competition rules may state a minimum number of players required to constitute a team, which is usually seven. Goalkeepers are the only players allowed to play the ball with their hands or arms, provided they do so within the penalty area in front of their own goal. Though there are a variety of positions in which the outfield (non-goalkeeper) players are strategically placed by a coach, these positions are not defined or required by the Laws.
What amount of players is not allowed?
---
Answer: unanswerable

Problem: Most of Hume's followers have disagreed with his conclusion that belief in an external world is rationally unjustifiable, contending that Hume's own principles implicitly contained the rational justification for such a belief, that is, beyond being content to let the issue rest on human instinct, custom and habit. According to an extreme empiricist theory known as phenomenalism, anticipated by the arguments of both Hume and George Berkeley, a physical object is a kind of construction out of our experiences. Phenomenalism is the view that physical objects, properties, events (whatever is physical) are reducible to mental objects, properties, events. Ultimately, only mental objects, properties, events, exist hence the closely related term subjective idealism. By the phenomenalistic line of thinking, to have a visual experience of a real physical thing is to have an experience of a certain kind of group of experiences. This type of set of experiences possesses a constancy and coherence that is lacking in the set of experiences of which hallucinations, for example, are a part. As John Stuart Mill put it in the mid-19th century, matter is the "permanent possibility of sensation". Mill's empiricism went a significant step beyond Hume in still another respect: in maintaining that induction is necessary for all meaningful knowledge including mathematics. As summarized by D.W. Hamlin:
Who argued for subjective idealism?
---
Answer: unanswerable

Problem: Ibn Tufail (Abubacer) and Ibn al-Nafis were pioneers of the philosophical novel. Ibn Tufail wrote the first Arabic novel Hayy ibn Yaqdhan (Philosophus Autodidactus) as a response to Al-Ghazali's The Incoherence of the Philosophers, and then Ibn al-Nafis also wrote a novel Theologus Autodidactus as a response to Ibn Tufail's Philosophus Autodidactus. Both of these narratives had protagonists (Hayy in Philosophus Autodidactus and Kamil in Theologus Autodidactus) who were autodidactic feral children living in seclusion on a desert island, both being the earliest examples of a desert island story. However, while Hayy lives alone with animals on the desert island for the rest of the story in Philosophus Autodidactus, the story of Kamil extends beyond the desert island setting in Theologus Autodidactus, developing into the earliest known coming of age plot and eventually becoming the first example of a science fiction novel.
Who wrote Theologus Autodidactus?
---
Answer:
Ibn al-Nafis