No. We are not able perfectly to understand immaterial substances through material substances because immaterial substances differ altogether in formal aspect from the definable structures of material things.
Per substantias materiales non possumus perfecte substantias immateriales intelligere quia substantiae immateriales sunt omnino alterius rationis a quidditatibus materialium rerum.
However much our intellect abstracts the definable structure of material things from matter, it could never arrive at anything similar to immaterial substance.
Quantumcumque intellectus noster abstrahat quidditatem rei materialis a materia, nunquam perveniet ad aliquid simile substantiae immateriali.
From material things we can rise to some kind of knowledge of immaterial things, but not to the perfect knowledge thereof, for there is no proper and adequate proportion between material and immaterial things; and the likenesses drawn from material things for the understanding of immaterial things are very dissimilar therefrom, as Dionysius says (Coel. Hier. ii).
Ex rebus materialibus ascendere possumus in aliqualem cognitionem immaterialium rerum, non tamen in perfectam, quia non est sufficiens comparatio rerum materialium ad immateriales; sed similitudines si quae a materialibus accipiuntur ad immaterialia intelligenda, sunt multum dissimiles, ut Dionysius dicit, II cap. Cael. Hier.
But we may have a scientific knowledge of them by way of negation and by their relation to material things.
Sed de eis nobis in scientiis documenta traduntur per viam remotionis et alicuius habitudinis ad res materiales.
Created immaterial substances are not in the same natural genus as material substances, for their formal aspect does not agree in power or in matter; but they belong to the same logical genus, because even immaterial substances are in the predicament of substance, since their definable structure is not their existence.
Substantiae immateriales creatae in genere quidem naturali non conveniunt cum substantiis materialibus, quia non est in eis eadem ratio potentiae et materiae; conveniunt tamen cum eis in genere logico, quia etiam substantiae immateriales sunt in praedicamento substantiae, cum earum quidditas non sit earum esse.
But God has no connection with material things, as regards either natural genus or logical genus; because God is in no genus, as stated above (Q3, A5). Hence through the likeness derived from material things we can know something positive concerning the angels, according to some common formal aspect, though not according to the specific formal aspect; whereas we cannot acquire any such knowledge at all about God.
Sed Deus non convenit cum rebus materialibus neque secundum genus naturale, neque secundum genus logicum, quia Deus nullo modo est in genere, ut supra dictum est. Unde per similitudines rerum materialium aliquid affirmative potest cognosci de Angelis secundum rationem communem, licet non secundum rationem speciei; de Deo autem nullo modo.