every philosophy of history as an _apocalypse._ Sometimes even a sort of revelation occurs in them, and we often find that the unthinkable connections of concepts constituting those pseudo-philosophies are obtained and comprehended in virtue of second sight, as the result of a mental illumination, which is the prerogative of but a few privileged persons. Finally, philosophism and mythologism embrace one another and fall embracing into empiricism and into the other forms of error previously described. [Sidenote: _Scepsis._] This perpetual transition from one form of error to another gives rise to a _scepsis,_ which promotes the reciprocal dissolution of errors, and scorning illusions and confusions, throws their _mental vacuity_ into clear light. Such a scepsis fulfils an important function. The lies of æstheticism, mathematicism, philosophism, mythologism, cannot resist it. Their little wordy strongholds are broken into; the shadows are dispersed. Especially against mythologism, which in a certain sense may be called the most complete negation of thought, a scepsis is helpful; and owing to the resistance offered here more than elsewhere, by passions and interests, it often takes the form of violent satire. The last great epoch of this strife is what is called the _Aufklärung,_ Encyclopedism or Voltaireism, and was directed against Christianity, especially in its Catholic form. We must make so many reservations in what follows concerning the enlightened Encyclopedist and Voltairean attitude, that here we feel obliged to indicate explicitly its serious and fruitful side. [Footnote 1: See with reference to this G. Gentile, _Il modernismo e l'enciclica, Critica,_ vi. pp. 208-229.] V DUALISM, SCEPTICISM AND MYSTICISM [Sidenote: _Dualism._]