What makes the part played by Florence in the history of learning the more remarkable is, that the chiefs of the political factions were at the same time the leaders of intellectual progress. Rinaldo degli Albizzi and Cosimo de' Medici, while opposed as antagonists in a duel to the death upon the stage of the republic, vied with each other in the patronage they extended to men of letters. Rinaldo was himself no mean scholar; and he chose one of the greatest men of the age, Tommaso da Sarzana, to be tutor to his children. Of Palla degli Strozzi's services in the cause of Greek learning I have already spoken in the second chapter of this volume. Beside the invitation which he caused to be sent to Manuel Chrysoloras, he employed his wealth and influence in providing books necessary for the prosecution of Hellenic studies. 'Messer Palla,' says Vespasiano, 'sent to Greece for countless volumes, all at his own cost. The "Cosmography" of Ptolemy, together with the picture made to illustrate it, the "Lives" of Plutarch, the works of Plato, and very many other writings of philosophers, he got from Constantinople. The "Politics" of Aristotle were not in Italy until Messer Palla sent for them; and when Messer Lionardo of Arezzo translated them, he had the copy from his hands.'[125] In the same spirit of practical generosity Palla degli Strozzi devoted his leisure and his energies to the improvement of the _studio pubblico_ at Florence, giving it that character of humane culture which it retained throughout the age of the Renaissance.[126] To him, again, belongs the glory of having first collected books for the express purpose of founding a public library. This project had occupied the mind of Petrarch, and its utility had been recognised by Coluccio de' Salutati,[127] but no one had as yet arisen to accomplish it. 'Being passionately fond of literature, Messer Palla always kept copyists in his own house and outside it, of the best who were in Florence, both for Greek and Latin books; and all the books he could find he purchased, on all subjects, being minded to found a most noble library in Santa Trinità, and to erect there a most beautiful building for the purpose. He wished that it should be open to the public, and he chose Santa Trinità because it was in the centre of Florence, a site of great convenience to everybody. His disasters supervened, and what he had designed he could not execute.'[128]