This library is built in the open.
If you spot an error, have a suggestion, or just want to say hello — we’d love to hear from you.

...by which he showed the first, the third by a third part, and so on. But the question is whether he has demonstrated this against his own position, as it follows from his own principle or premise. He attempts in vain to throw back the absurd conclusions leveled against him. He acts as if it is the same whether he compares distance or time with velocity. When he argues against his opponent, he wanders astray at the very threshold. He does this by assuming something that is not stated at all, and by comparing time with velocity in a way other than how it should be compared. All the boasting that follows contains nothing to be envied. While he says that the attack on his reasoning is empty and vain, and can only find applause among the less skilled, it is enough to challenge him to produce even a single skilled person whom he can persuade of his opinion.
The Reverend Father original: "R. P." for "Reverendus Pater," referring to Marin Mersenne proved that the velocity through the second part is double the velocity through the lower half of the first part for no other reason than because the distance is double. He did not prove this consequence in any way. Instead, he only assumed it based on the idea that velocities are as the distances. This is a repeated begging of the question begging of the question: a logical fallacy where the conclusion is assumed in the premises. This is the very point in dispute. It is not shown to be true anywhere, except from that false experiment involving the Balance original: "Bilancem experimento," referring to Mersenne's use of scales to measure the force of falling weights. One objection was chosen to be answered because of a slip of the pen original: "errore calami", where one letter crept in for another in an immense and troublesome heap of correspondence. The Reverend Father is fortunate that the Author does not seem to have entered into the inner secrets of the controversy, and that the Author keeps him as far from his own sayings as from the nature that must be inspected more deeply. The time of six minutes attributed to the first...