in the same measure as

"But I suspect that this characteristic excitement (...) is not the source, but the effect, of artistic labor, the personal emotive experience of revelation, insight, mental power, which an adventure in 'implicit understanding' inspires. It has often been stated that it is the same emotion which overtakes a mathematician as he constructs a convincing and elegant proof; and this is the beatitude which Spinoza (...) called 'the intellectual love of God.' Something like it is begotten in appreciation of art, too, though not nearly in the same measure as in producing; but the fact that the difference is one of degree makes it plausible that the emotion springs from the one activity which the artist and the beholder share in unequal parts -- the comprehension of an unspoken idea." (Susanne K. Langer, Philosophy in a New Key).

Could you please rephrase the blue clause and explain the meaning of "one of degree?"

Thank you.

cadzao