Post: For parashat Miketz, Abarbanel discusses at length what causes dreams. Are they direct messages from Hashem, caused by celestial influences, by what is churning through one's mind during the day, or a result of a combination of man's imaginative faculty influenced by whichever of the four humors is prevailing. (He eventually concludes "all of the above", that different dreams are products of different causes.) The entire discussion is worth a read, but I'll just roughly translate the relevant quote:
This is, of course, a reference to the scientific belief in the four humors, which was the science of Abarbanel's day. We know that he is taking into account the science of his day rather than, say, knowing the truth via Divine revelation or correct derashot from pesukim because that science was wrong. Which is lucky for us, I say, because otherwise it wouldn't serve as good precedence for Torah UMaddah.
Abarbanel lived from 1437 - 1508. Geoffrey Chaucer lived from 1343 - 1400, which puts him more of less contemporary, in the time of the Rishonim. Here is a quote from "The Nun's Priest's Tale of the Cock and the Hen", part of Chaucer's Canterbury Tales: (the phrases marked in asterisks are translated at the side)
Alas! and can ye be aghast of swevenes?* *dreamsOr, from the Portable Chaucer, a nice translation of Chaucer into modern English, we read:
Nothing but vanity, God wot, in sweven is,
Swevens *engender of repletions,* *are caused by over-eating*
And oft of fume,* and of complexions, *drunkenness
When humours be too abundant in a wight.
Certes this dream, which ye have mette tonight,
Cometh of the great supefluity
Of youre rede cholera,* pardie, *bile
Which causeth folk to dreaden in their dreams
Of arrows, and of fire with redde beams,
Of redde beastes, that they will them bite,
Of conteke,* and of whelpes great and lite;** *contention **little
Right as the humour of melancholy
Causeth full many a man in sleep to cry,
For fear of bulles, or of beares blake,
Or elles that black devils will them take,
Of other humours could I tell also,
That worke many a man in sleep much woe;
That I will pass as lightly as I can.
Lo, Cato, which that was so wise a man,
Said he not thus, *'Ne do no force of* dreams,' *attach no weight to*
Now, Sir," quoth she, "when we fly from these beams,
For Godde's love, as take some laxatife;
On peril of my soul, and of my life,
I counsel you the best, I will not lie,
That both of choler, and melancholy,
Ye purge you; and, for ye shall not tarry,
Though in this town is no apothecary,
I shall myself two herbes teache you,
That shall be for your health, and for your prow;* *profit
And in our yard the herbes shall I find,
The which have of their property by kind* *nature
To purge you beneath, and eke above.
The parallels are obvious, and are to be expected.