I am wondering why Leonard Nelson does not come up in philosophy. There might be one reason that Husserl accused him of psychologism. But I think that was not accurate. It might be we look into our minds to see first principles [empirically], but these first principles we know not from empirical evidence but non intuitive immediate knowledge. 

Especially after Husserl himself does not seem so great. [As Michael Sugrue pointed out.] And in fact most of "Analytic Philosophy" seems to be off track as Robert Hanna has pointed out. I only read some of one of his books about  how "Analytic Philosophy" is ready for the trash bin. But his arguments are very convincing.

The only exception I have to Nelson [who is based on Fries] is the complete dismissal of Hegel which I think is too much based on Hegel's politics which was in reaction to the French Revolution.]

Just as a side note I should add here why I think Nelson is important. Part of the reason is public--that is this: There are problems in Kant that I think Fries and Nelson do the best job in answering. I mean even if we would agree with Robert Hanna about "Forward to Kant," those problems would remain. So you can do some modification and that would be with the Friesian school. 

Another reason is personal--while in Safed in Israel I had what many people in history have had- this sort of "Enlightenment" kind of experience. This indicated a whole new dimension of reality that is not available to empirical knowledge nor to Reason. So it made sense to me to see that there is a different source of knowledge besides pure reason or the senses--immediate non-intuitive knowledge.