Do you want me to spell it out for you?
1. A logical argument with an assumed premise is unsound.
2. A logical argument that is unsound is fallacious.
3. All presuppositionalist arguments have assumed premises.
Therefore:
4. All presuppositionalist arguments are fallacious.
1. A logical argument with an assumed premise is unsound.
2. A logical argument that is unsound is fallacious.
3. All presuppositionalist arguments have assumed premises.
Therefore:
4. All presuppositionalist arguments are fallacious.
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