> Philosophy’s logical conclusions are relativism and nihilism
Some philosophers, notably Jacobi [1], have argued this (he is credited with popularizing the term nihilism). He was arguing against enlightenment thinkers, especially Spinoza and Kant (and the rest of German Idealism). But one philosopher's conjecture isn't equal in any sense to some unequivocal stance of "Philosophy". It is worth noting, that he was arguing for "Faith" instead of speculative reason, so maybe not what you would think.
So your point is true in a very limited sense. Some philosophers have argued against some particular philosophies by suggesting that the particular philosophy they are criticizing is likely to lead to relativism and nihilism.
Some philosophers, notably Jacobi [1], have argued this (he is credited with popularizing the term nihilism). He was arguing against enlightenment thinkers, especially Spinoza and Kant (and the rest of German Idealism). But one philosopher's conjecture isn't equal in any sense to some unequivocal stance of "Philosophy". It is worth noting, that he was arguing for "Faith" instead of speculative reason, so maybe not what you would think.
So your point is true in a very limited sense. Some philosophers have argued against some particular philosophies by suggesting that the particular philosophy they are criticizing is likely to lead to relativism and nihilism.
1. https://en.wikipedia.org/wiki/Friedrich_Heinrich_Jacobi