"You must consider, when reading this treatise, that mental perception, because connected with matter, is subject to conditions similar to those to which physical perception is subject"

Maimonides is suggesting that mental understanding, which is linked to matter, goes through the very same conditions as physical assumption. He is implying that mental understanding is not separate from physical assumption, but instead is linked with it. He is suggesting that the exact same laws of nature that control physical perception additionally govern mental understanding. He is stressing that psychological understanding is not some abstract idea, but instead is subject to the exact same laws of nature as physical understanding. He is recommending that need to take into account the physical conditions when considering mental understanding. He is stressing that mental understanding is not some abstract concept, but instead goes through the exact same legislations of nature as physical understanding. He is recommending that one should take into account the physical problems when taking into consideration psychological perception. He is stressing that psychological assumption is not some abstract principle, but rather undergoes the same regulations of nature as physical understanding. He is recommending that a person must take into consideration the physical problems when reading his writing on psychological perception.