Will and power. Dante would fain thank the spirit that has addressed him, but knows not how. He has the will, but not the power. Dante uses the word argument in this sense of power, or means, or appliance, Purgatorio II 31:⁠—

“See how he scorns all human arguments,

So that nor oar he wants, nor other sail

Than his own wings, between so distant shores.”

“See how he scorns all human arguments, So that nor oar he wants, nor other sail Than his own wings, between so distant shores.”

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